|
July 2002 Forecast Outlook, Discussion
& Report Page
Victoria |
Date |
Name |
Information |
31 |
. |
Overview: An area
of moderate but declining high pressure over eastern New South Wales and the Tasman Sea
cradles a 'cut-off'(?) surface trough of low pressure off the central New South Wales
coast. The trough over Queensland remains inland from a ridge extending along the coast,
with the trough moving east during Tuesday, with thunderstorms in central Queensland
during the day. A trough and front is
crossing Western Australia with tropical moisture originating from north of Indonesia
feeding into this system across the west coast south of the Pilbara. The Cape York and
northeast of the Top End are seeing increasing moisture levels, as is eastern Australia
generally. A high in the Indian Ocean is ridging towards the west of the continent between
30 and 35°S.
Discussion: The upper trough
over Queensland will move off the coast during Wednesday, and the surface trough over the
Tasman is likely to weaken. A moist onshore flow will trigger showers over the
northern New South Wales and southern and central Queensland coasts. The high, which
was cradling the Tasman trough during Tuesday will ridge to the northwest through New
South Wales. Cold nights and widespread frosts are expected over southeastern Australia on
Tuesday night.
The trough and frontal system over Western
Australia will move into South Australia during Wednesday - a satellite low in the
southwest Bight will move northeast initially on Wednesday around around the deep low in
the Southern Ocean. The high will ridge in across southern Western Australia.
Rainfall potential
Victoria: Increasing high cloud over the southwest. A cold night
with widespread frosts, some severe, especially in the west, north and along the ranges. A
mainly fine day with some fog patches in the south lingering.
NSW: Showers along the coast in a moist southerly flow, mainly in the north.
A cold night in the south with frosts, with some possibly severe over higher parts.
Queensland: Possible isolated storms in the east Tuesday night, clearing.
Isolated showers over much of the coast as well as Cape York, with the chance of a storm
over the central ranges during Wednesday.
NT: Mainly fine with the chance of shower over the northeast and morning fogs
over parts of the Top End.
WA: Fine in the north. Showers over the west coast and southern parts,
moving east Tuesday night and through Wednesday with the trough and front. Isolated
showers lingering in the south and southwest in the onshore flow.
SA: A cold night, particularly in the east, with widespread frosts. Showers
developing later in the day with the approach of the trough and front, mainly in the
south, mostly not reaching the ground.
Tasmania: A cold night with widespread frosts, and some fog patches.
Strengthening northwesterly winds later in the day with increasing cloud in the west.
Fine in the east. |
30 |
. |
Overview: A trough,
supported by an upper low, has its centre over southern Queensland with a dryline
extending along the western side of the Great Divide to Cape York being evident during the
afternoon. The trough also extends to the southeast through northern New South Wales and
joins to a pair of fronts in the central Tasman Sea. Storms this afternoon have extended
from as far south as near Sydney, over the northeastern corner of New South Wales, and
through southern Queensland under the influence of this extensive trough........it's
almost spring! A high of medium strength is
located in the head of the Bight, while a trough and front approaches the southwest of
Western Australia at the leading edge of the next longwave trough. Some upper cloud
is evident of high level moisture feeding in from the Indian Ocean across the Pilbara
coast and then to the northeast - cloud, but no rain.
Discussion:
A trough, supported by an upper low, has its centre
over southern Queensland with a dryline extending along the western side of the Great
Divide to Cape York being evident during the afternoon. The trough also extends to the
southeast through northern New South Wales and joins to a pair of fronts in the central
Tasman Sea. Storms this afternoon have extended from as far south as near Sydney, over the
northeastern corner of New South Wales, and through southern Queensland under the
influence of this extensive trough........it's almost spring!
A high of medium strength is located in the head of
the Bight, while a trough and front approaches the southwest of Western Australia at the
leading edge of the next longwave trough. Some upper cloud is evident of high level
moisture feeding in from the Indian Ocean across the Pilbara coast and then to the
northeast - cloud, but no rain.
Discussion: The trough
over eastern Australia will weaken through later Monday and Tuesday but remain over the
southern part of Queensland, and move east later Tuesday. A further trough will
deepen off the New South Wales coast. The high in the Bight will move east across the
southeastern part of the continent, and while ridging to the northwest, will cradle the
trough to its north. Little pressure change over southeastern Australia is likely
for at least the next 24 hours, and the baric ridge will remain near 35°S and the baric
trough through the Southern Ocean near to 60°S.
Showers will continue along the Queensland coast
while isolated storms will be likely under the influence of the trough, mainly in
Queensland and the far northeastern corner of New South Wales.
Light winds over much of southeastern and central
Australia will mean a return to cold nights, particularly inland, with strong radiational
cooling under the influence of this high. The trough and front will move fairly quickly
through southern parts of Western Australia during Tuesday, with showers also extending
north along the west coast. An extensive infeed of tropical moisture into this
trough from the Indian Ocean may help this trough deepen further.
Rainfall potential
Victoria: Only patchy cloud, mainly in the south and along the eastern
ranges overnight. A cold night with widespread frosts. A fine day to follow,
with patchy cloud about the ranges.
NSW: Isolated showers and storms near the central and north coasts Monday
night, contracting northeast. Cold nights inland, mainly in the south. Drizzle patches on
the windward slopes of the ranges, mainly in the south.
Queensland: Showers and scattered storms, mainly in the south and near the
central ranges, moving east with the trough. Fine in the west of the state.
Showers along the east coast.
NT: Possible isolated showers over the northeast Top End, some patchy high
cloud extending through the Territory from the west.
WA: Showers and possible storms in the southwest with the trough and front,
extending north along the west coast. Some high cloud over the Pilbara and western
Kimberley.
SA: Mainly fine throughout after a cold night with widespread frosts mainly
in the southeast. A fine day with light winds.
Tasmania: Mainly fine after clearing showers in the west. A cold night
with widespread frosts with fogs more generally in the east. Cloud increasing later
Tuesday / Wednesday with the approach of the next front. Northwesterly winds
strengthening. |
29 |
. |
Overview: The
prefrontal trough moving across the continent during this weekend has retained its
identity and is located through Victoria. southwestern New South Wales and northeastern
South Australia on Sunday afternoon, with the front following not far to its west. Weak
infeed to the trough is still apparent from the Indian Ocean. Scattered showers with falls
of up to 20mm have been recorded in South Australia and western Victoria during the
weekend. As midlevel temperatures dropped through Sunday afternoon, light snowfalls have
been recorded on the higher parts of the Victorian Alps from mid afternoon. The ridge of high pressure has remained over eastern
Australia from a slow moving high to the southeast of New Zealand. A moderate strength
high has become established over the southern coast of Western Australia. The area of
lower pressure that has been over the far north of the Territory remains.
Discussion: The front
is likely to slow as it moves through the southeast of the continent, while the trough
will deepen ahead of it over New South Wales. The high over Southern Western Australia
will move steadily east across the head of the Bight while the baric trough remains near
to 60°S again.
The ridge along the Queensland coast will remain
through Monday with showers over much of the coast. Much of New South Wales will be under
cloud, with scattered showers under the influence of the slow moving trough. Southern
parts of Queensland will also be influenced by this trough and will see isolated
showers becoming more widespread into Tuesday and moving east. Another front will
approach Western Australia Tuesday bringing widespread showers to the southwest.
Rainfall potential
Victoria: Showers over the Alps Sunday afternoon / Monday falling as
snow. Scattered showers elsewhere Sunday contracting to the south and east and
becoming isolated.
NSW: Showers in the south, falling as snow over the Alps. Scattered
showers developing in the north later Monday and into Tuesday.
Queensland: Isolated showers developing in the south, with the chance of a
storm, under the influence of the trough moving through eastern Australia. Showers along
most of the eastern coast.
NT: Mainly fine throughout.
WA: Some high cloud over northern parts of the state, but remaining fine.
Strengthening northwesterly winds on Monday night / Tuesday ahead of a front.
SA: Scattered showers in southern districts, mainly along the coast, then
clearing and becoming fine throughout under the influence of a ridge moving from the west.
Tasmania: Showers, with snow over higher parts, clearing from the west
Sunday night. Only isolated showers remaining mainly in the west through Monday. |
28 |
. |
Overview: A ridge
of high pressure over New South Wales from a strong high southeast of New Zealand, extends
along the Queensland coast (is this the first Queensland ridge of the season?), while an
area of low pressure is located over the Top End. An intensifying trough precedes the
front currently moving into South Australia and is gaining tropical moisture from the
Indian Ocean. A thermal trough to the west of the front is moving through the western
Bight. The high ridging along the southern coast of Western Australia has weakened as it
moved east. Two lows in the Southern Ocean near to 60°S are 949hPa and 955hPa. Discussion: The ridge of high
pressure will remain over eastern New South Wales while edging westward over Queensland.
The prefrontal trough will continue to draw some moisture from the Indian Ocean. The front
will move through the southeastern corner during Saturday night to Sunday night
while the ridge over eastern Australia will weaken and contract to the southeast.
Colder air to the west of the front and associated
with the thermal trough will become more generally established over southern Australia
during Sunday and Monday. The new centre of high pressure will move along the southern
coast and is likely to be near the head of the Bight by Sunday night and maintain its
strength.
Rainfall potential
Victoria: Cloud increasing in the west Saturday night ahead of the front
with showers developing and spreading east through Sunday. A mild day
becoming cooler with scattered showers, mainly in the south and on the ranges, falling as
snow on the Alps, with the snow level lowering later as colder air becomes established.
NSW: Winds becoming northwesterly ahead of a front moving through much of the
south of the state during Sunday. Showers developing in the south, falling as
snow over the Alps.
Queensland: Isolated showers over Cape York and the far northeastern tropical
coast becoming more widespread over much of the coast during Sunday. A cold night inland
with some frosts in the south.
NT: Isolated showers about the northeast coast. Fine elsewhere.
WA: Only isolated showers during Sunday in the southwest of the state, with
showers in the southeast clearing on Saturday night. A cold night in the south.
SA: Showers in the south and southeast, occasionally heavy during Saturday
night and early Sunday, clearing to isolated showers during Sunday. Possible storms in the
south in the colder air behind the front.
Tasmania: Cloud increasing in the west. Showers (with the chance of a
storm in the west), becoming more widespread and spreading east during Sunday. Showers
will become more isolated in the east later in the day. |
27 |
. |
Overview: A high of
moderate strength (1022hPa) is located over northeastern New South Wales, with a broad
trough to the southwest covering the entire Bight. A low of 978hPa is located near
to 45°S and is 'satellite' to a deep low further south near to 60°S of 949hPa which
extends 2 fronts to the north. The low in the Tasman Sea is near the North Island of New
Zealand and is still analysed as full-depth. Two areas of upper cloud have appeared over
Western Australia and inland South Australia which mark the location of the upper
jetstream across the continent. An infeed of moisture in the upper levels from near Timor
is approaching the western Kimberley while the moisture levels over Cape York and the Top
End are also showing a slight increase. The high over the Indian Ocean has weakened
slightly. Discussion: The
high over New South Wales will remain slow moving through Saturday The surface low in the
Bight will continue to satellite around the deep low to the south. A prefrontal
trough and front will cross Western Australia and much of South Australia during Saturday.
The Indian Ocean high will ridge in across southern Western Australia behind the frontal
system. Widespread showers are likely with and behind this front, particularly over
southern parts of Western Australia and in the cold air following.
Northwesterly winds will strengthen over the
southeast ahead of the front as the pressure gradient tightens between the high and the
front during Saturday. The deepening of the prefrontal trough and greater moisture infeed
from the Indian Ocean may lead to some heavy falls during later Saturday. Much of
Australia north of the baric ridge (~ 30°S) will remain fine except for some coastal
areas in the far north.
Areas to watch: The cold
pool in the western Bight is being driven northeast around the upper trough by the polar
jet should be watched to see where it makes landfall.
Rainfall potential
Victoria: Increasing northwesterly winds in the west through Saturday.
Isolated showers developing in the southwest. Showers developing about the Alps falling as
snow later in the weekend.
NSW: A cold night inland with frost over higher parts, especially in the
north. Strengthening winds and increasing cloud in the south, with showers falling as snow
developing later.
Queensland: Isolated showers about Cape York. Mostly fine elsewhere.
NT: Mainly fine except for the northeast corner of the Top End where there may
be isolated showers.
WA: Scattered showers with a front crossing the southwest Friday night and
moving east. Showers, along the coast and inland near the coast, becoming isolated
to the west. Fine in the north with some high cloud over the Pilbara.
SA: Strengthening northwesterly winds ahead of a front moving through much of
the state during Saturday. Scattered showers with the front becoming isolated to the
west. Possible storms with hail in the south behind the front.
Tasmania: Strengthening northwesterly winds ahead of the front.
Scattered showers in the west, spreading east and falling as snow about the higher peaks
during Sunday. |
26 |
. |
Overview: The high
pressure centres over eastern Australia remain sandwiched between the low which deepened
through Thursday in the Tasman Sea to ~1002hPa at 4pm (ex cold pool from the Bight earlier
in the week) and the fronts encroaching upon the southeastern corner of the continent.
These fronts are on the eastern side of the trough in the Bight. The southern centre of
high pressure, now to the southeast of Tasmania has created a cut-off situation for the
the low in the Tasman. The baric trough remains between 50 and 55°S across our
longitudes (965 and 969hPa at 4pm AEST). A very strong high (1040hPa!!) is approaching
from the Indian Ocean - analysis at 10am on Thursday showed that it was influencing the
region from Madagascar to Western Australia (see here) Moisture feeds towards the northeast of the continent from a
complex area of convection in the northern hemisphere. Humidities have risen over Cape
York and the Top End as a result of this infeed. Away from the coast, much of central and
northern Australia remains cloudfree.
An area of vorticity is located in the
central Bight west of Tasmania.
Discussion: The highs
over the eastern Australian longitudes will continue to edge eastward with the
southernmost centre moving east more rapidly than the centre over New South Wales. The low
in the Tasman will gradually weaken as it moves east. The low in the southwestern Bight is
likely to track northeast for a period on Friday as it 'satellites' around the low to its
south - there is another area of vorticity to its north - see 'Areas to watch' below.
A front will cross the southwest of Western
Australia during Friday bringing showers to the southwest, while the strong high in the
Indian Ocean looks to weaken as it moves towards the west coast.
Areas to watch: The area of
vorticity in the Bight located near ~43°S (at 8pm Thursday night) for movement towards
the northeast. Looks most likely to 'satellite' around the low in the southern Bight., but
may move northeast initially.
Rainfall potential
Victoria: Scattered showers moving from the west during Thursday night,
then clearing from the west on Friday. Snow developing on the Alps later Friday.
NSW: Cold nights along the tablelands with widespread frosts in the north
ahead of the cloudband moving through the south of the state. Showers in the south with
the front, falling as snow on the Alps later.
Queensland: Mainly fine except for the far northeast tropical coast and Cape
York which may see isolated showers. Cold nights along the ranges with frosts likely in
the south.
NT: Cloudy periods along the northeast coast with isolated showers. Fine
elsewhere.
WA: Northwesterly winds strengthening in the southwest of the state ahead of
a front. Scattered showers becoming more widespread through the south for a brief
period then contracting to the far southwest again and becoming isolated.
SA: Isolated showers along the exposed parts of the coast. Fine
elsewhere. Overnight fogs likely in the southeast.
Tasmania: Widespread showers in the west Thursday night spreading to the east
during Friday but becoming isolated. Light snow later over higher peaks, mainly in the
west. |
25 |
. |
Overview: The high
has been edged south to lie near 42°S to the west of Tasmania on Wednesday night and
ridges strongly into the Northern Territory and southward to the Southern Ocean. The area
of vorticity and cold pool that crossed Victoria on Tuesday night is now moving through
eastern New South Wales. A trough and series of fronts is crossing the southwest corner of
Western Australia with an area of middle level cloud being drawn into an area of potential
vorticity south of Esperance on Wednesday night. Tropical moisture from the Indian Ocean
crosses the Pilbara coast and feeds into this system. Discussion: The area of vorticity / cold
pool moving across New South Wales is likely to deepen into a low as it moves into more
favourable conditions over the Tasman Sea. The high pressure over eastern Australia will
remain 'sandwiched' between the developing low in the Tasman and the front in the Bight
during Thursday while continuing to move east. The baric trough is likely to move
north again to lie near to 55°S in the southern Bight southwest of the high under a broad
upper trough. A strengthening high over the Indian Ocean will approach the west of the
continent during Friday. Cross equatorial moisture is crossing the northeast of the
continent and being drawn into the 'shear zone' over the Coral Sea, before heading
southeast.
Areas to watch: Congesting cumulus
have been sighted over the Top End!! No, not an early start to the 'Buildup', this is a
normal sign that a change in the pattern is not too far away.
Rainfall potential
Victoria: A cold night in areas under clear skies. Isolated fogs in the
south. A full-height (as in surface to tropopause) ridge moving through the west of the
state overnight Wednesday and early Thursday with strong warm advection through the middle
levels ahead of the front approaching from the Bight later Thursday / early Friday.
Showers in the far east clearing Thursday, with showers redeveloping during the afternoon
in the west and spreading to central areas later.
NSW: A cold night inland under clear skies. Scattered showers with and
following the trough moving through the central coast and tablelands Wednesday night and
the northeast of the state early Thursday. Showers becoming isolated through Thursday.
Queensland: Isolated showers over the far northeastern tropical coast and Cape
York. Dry elsewhere.
NT: An increase in humidity along the northern coast may lead to isolated
showers along the northern and eastern Top End coasts. Fine elsewhere.
WA: Possible isolated showers in the Pilbara and Eucla. Showers with isolated
storms associated with a front crossing the southwest during Thursday.
SA: Increasing cloud in the west, spreading east to reach the southeastern
border later in the day. Strengthening northwesterly winds ahead of the front with
scattered showers, mainly in the south. Isolated showers along the exposed coasts
following the front. Cold night inland.
Tasmania: Scattered showers Wednesday night with isolated light snowfalls.
Conditions clearing except in the south of the state where scattered showers remain
likely. A cold night with widespread frosts. Strengthening northwesterly winds in
the west with conditions becoming milder ahead of the front. |
24 |
. |
Overview: The baric
ridge has continued to 'see-saw' through Tuesday with the eastern section remaining north
of 30°S and weak, while a new centre of high pressure has formed in the northern Bight.
The low near New Zealand has remained slow moving with some substantial falls being
recorded over parts of the North Island. The
development of an area of vorticity near Mt Gambier in the trough moving across the
southeast of the continent has triggered scattered storms with some heavy falls in
southwest Victoria later Tuesday, with more likely through Bass Strait and over northern
Tasmania tonight and early Wednesday.
A weak plume of tropical moisture has reached south
through the Arafura Sea to the Top End of the Northern Territory, and can be traced as far
east as Cape York.
Discussion: The low
near New Zealand will begin to weaken through Wednesday. The area of vorticity near Mt
Gambier is likely to move in a generally easterly direction & looks to enhance shower
and storm activity over the Bass Strait area and adjacent coasts Tuesday night and into
Wednesday.
The high in the Bight will move slowly east through
Wednesday, while an upper ridge will also move across the southeast of the continent - the
combination of both surface and upper highs will bring a return to rather more stable
weather (although not necessarily clear skies) to much of the southeast following the
passage of the front / trough. In general, the continent north of the baric ridge, remains
mainly fine with only patchy cloud in northeastern coastal areas and isolated showers over
the northeast Top End and the northeast tropical coast of Queensland.
The longwave trough approaching the southwest of
Western Australia continues to deepen as it moves east, while the thermal trough to its
west extends its influence to near 25°S over the Indian Ocean.
Areas to watch: An area of middle
level cloud has formed over southern Western Australia and should be watched for the next
24 hours......it seems to be linked to the trough currently passing across the southeast
and marks a weak baroclinic zone.
Rainfall potential
Victoria: Isolated storms in the south on Tuesday night with the passage
of the front, with the chance of hail. Showers with isolated heavier falls in much
of the west of the state Tuesday night, extending east overnight and then clearing through
much of the state during Wednesday. Snow on the peaks.
NSW: Patchy rain developing in the south, falling as snow over the higher
peaks. A deep south-southwesterly flow developing behind the front with scattered showers,
mainly in the south. Remaining mainly fine in the north until later in the day.
Queensland: Isolated showers along the northeast coast and Cape York.
Fine elsewhere.
NT: Chance of isolated showers in the northeast. Fine elsewhere.
WA: Strengthening northwesterly winds in the southwest ahead of a front which
will move across much of the southern parts during Wednesday. Scattered storms in
the south with some heavy falls possible, mainly near the coast. Fine in the north.
SA: Becoming fine after scattered showers and isolated storms in the
southeast during Tuesday night, clearing as the high becomes established in the Bight.
Increasing cloud in the west of the state as the next front approaches on Thursday.
A cold night with frosts inland.
Tasmania: Showers in the north and east Tuesday night with the likelihood of
isolated storms, especially near Bass Strait. Snowfalls at higher levels early.
Clearing during Wednesday with only isolated showers remaining in the east later. |
23 |
. |
Overview: The high
remains over southeastern New South Wales and has begun to weaken. This high extends
a ridge to the southeast towards New Zealand, cradling the low which is slow moving as
well as slow deepening near the northwest of the North Island. The trough in the Tasman
Sea, which is identified from the surface to the tropopause, has deepened at all levels
and slowed its eastward movement. The front in the Bight is also very slow moving - in
fact it seems that the entire Australasian area is under a "synoptic go-slow".
High cloud coming into the west of
the Bight is responding to a strengthening of the sub-tropical jet south of Western
Australia, while the large area of cloud over southeastern Australia is mostly middle and
upper level, marking the location of a weak upper trough, with only isolated light falls
during Monday in the west of Victoria and the southeast of South Australia.
Moisture over the equatorial area east of 140°E is
steadily moving south towards tropical eastern Australia.
Discussion: The high
over eastern Australia will weaken and edge northward during Tuesday, while there will be
a strengthening of the high to the west and a seesaw effect with the western section of
the baric trough slipping southward. A weak front will follow the middle level
trough and cross the southeastern corner with scattered light showers & some further
falls of snow above 1450m over the Alps. This middle level trough is still feeding some of
its moisture from the Indian Ocean, but this flow is continuing to weaken.
A deep low near to 55°S (964hPa at 10am EST)
southwest of Western Australia is bringing substantially colder air from the Southern
Ocean and looks to affect the southeast of the continent and Tasmania late in the week.
Rainfall potential
Victoria: Scattered light showers or drizzle in the west extending east,
but mainly on and south of the ranges. Showers becoming more isolated during Tuesday with
the passage of the front with scattered snowfalls over the Alps above 1450m.
NSW: The passage of the front will trigger scattered falls, mainly in the
south falling as snow over the Alps above 1450m. Only isolated showers elsewhere. Frosts
are likely over areas experiencing clear conditions ahead of the approaching cloudband.
Queensland: Isolated showers over the northeast tropical coast. Cloud
increasing through the south of the state, but little if any rain is likely.
NT: Isolated cloud over the northeast, with the chance of a shower.
Patchy high cloud in the south. Any showers from this cloud are not likely to reach
the ground.
WA: Fine in the north, only isolated showers in the south except over the
Southwest Capes early Tuesday where falls may be more scattered. Cloud increasing in the
southwest ahead of the next front, with strengthening northwesterly winds.
SA: Showers in the southeast Monday night. Cloud and showers increasing in
the south with the passage of a weak front during Tuesday with only isolated showers away
from the coast, mostly not reaching the ground.
Tasmania: Cloudy. Showers in the west, tending to periods of rain and
spreading east, before becoming scattered Tuesday. Possible snow over higher parts behind
the passage of the front during Tuesday. |
22 |
. |
Overview: A high
remains over southeastern Australia with stable conditions reinforced by the upper high
just to its northwest. The trough which passed over New South Wales has moved away from
eastern Australia and is located in the Tasman Sea and beginning to show signs of
cyclogenesis. The baric trough (South Ocean
lows) remains near to 60°S while the baric ridge across the continent is located near to
35°S and is becoming weaker in the Indian Ocean. The front passing through the Bight has
captured the trough which has been moving slowly southeast towards the west coast for the
past few days and on Sunday afternoon it was located just south of Esperance with a
thickening of the cloud band.
Discussion: The high
over eastern Australia may strengthen slightly but will remain slow moving through Monday
with widespread frosts overnight Sunday, some severe, in cloud free areas of the
southeast, particularly away from the coast and at higher levels. This high will cut the
low likely to form in the Tasman Sea near New Zealand off.
A weak upper trough will pass through the Bight
during Monday which may help to intensify the surface trough as it moves east - weak
infeed from the subtropical Indian Ocean into this system is likely to continue.
A deep low well southwest of Western Australia
(963hPa 10am AEST) will move into the southern Bight during later Tuesday / Wednesday,
bringing with it significantly colder air from the Southern Ocean and affecting the
southwest of Western Australia midweek.
Areas to watch: The trough and
cloud area over the Bight on Sunday night as it moves east for signs of development for
the next 24 hours. The cross equatorial moisture surge may trigger less isolated showers
than we have seen across the northeast of the Top End and Cape York.
Rainfall potential
Victoria: A cold night under clear skies. Frosts, particularly
north of the ranges, some severe. High cloud increasing from the west during Monday, only
isolated showers along the southwest coast.
NSW: Mainly fine across the state with light winds and widespread frosts in
cloudfree areas, some severe. A fine day with only the chance of an isolated shower
in the far northeast later in the day.
Queensland: Scattered showers over Cape York and the northeast tropical
coasts. Fine elsewhere.
NT: Isolated showers possible about the northeast coast. Fine
elsewhere.
WA: Fine in the north of the state. Only isolated coastal showers in
the far southwest corner. Possible showers early in the southeast as the trough moves out
of the state.
SA: Increasing high cloud, showers in the west mainly not reaching the
ground. Fogs in the southeast.
Tasmania: Scattered showers in the south and west on Monday, increasing
through the day with the approach of a front. |
21 |
. |
Overview: A front
crossed the southeast corner during Saturday with a middle level cold pool moving across
southern Victoria triggering hail in the south & sleet and snow at higher levels.
Mt Buller reported thundersnow this afternoon!! A weak surface trough is located
near Sydney ahead of the front which is over the southeast corner of New South Wales on
Saturday afternoon. A high is located in the
head of the Bight (a bit far south for this time of the year) and to its west the trough
off the coast of Western Australia remains quasi-stationery with widespread, but only very
light falls are reaching the ground in the west of the state as far north as the Pilbara.
The Southern Ocean lows (baric trough) - 951hPa at 10am AEST, have correspondingly moved
south and now lie close to 60°S. A weak area of moisture over the Timor Sea is
approaching the Kimberley coast.
Discussion: The high will
strengthen and move east to lie over the southeast of the continent, bringing the
expectation of very cold conditions during Saturday night north of the ranges in Victoria
and in the east of South Australia. The front over the southeastern corner of New
South Wales will move northwards along the coast and colder air will become established
over the southeast of the state and extend further north along the coast and adjacent
ranges to near the Queensland border.
The trough off the west coast will be captured by
the front moving towards the southwest of Western Australia during Sunday, and this will
help feed more moisture onto the coast initially before the system weakens later in the
weekend. Another high will approach the west early in the new week.
Areas to watch: We may see a cross
equatorial surge of moisture across Cape York and into the Coral Sea during the next 72
hours.
Rainfall potential
Victoria: Winds decreasing except over the Alps. Scattered showers
along the ranges falling as snow at higher levels. Isolated showers along the coast
clearing through Sunday. A cold night north of the ranges with scattered severe
frosts.
NSW: Showers in southern and coastal regions during Sunday morning, falling
as snow over the Alps. Showers likely to extend north during the day along the ranges and
coast. Isolated storms are possible. Mainly fine in the north away from the coast.
Queensland: Isolated showers along exposed parts of the northeastern tropical
coast & over the north of Cape York.
NT: Scattered cloud over the northeast and west. Only isolated showers
likely in the northeast.
WA: Light falls continuing along the west coast, and in the southwest,
spreading east and becoming isolated in the west later Sunday.
SA: Isolated showers over exposed coasts. Cold night inland,
particularly in the east with frosts.
Tasmania: Showers continuing in the west and north, showers in other parts of
the state clearing during Sunday. Snowfalls over higher parts Saturday night and
early Sunday, becoming isolated later at higher levels. Scattered showers continuing in
the southwest. |
20 |
. |
Overview: The baric
ridge runs near to 30°S (further north in the east), with a centre of high pressure over
northeast New South Wales and the Tasman Sea. A front extending from a low southeast
of New Zealand (969hPa at 10am AEST) to central Western Australia bisects the baric trough
over Western Australia. The front crossing southeastern Australia is weakening as it moves
east. A low of 972hPa is located in the central southern Bight and extends a cold front
through the northwest Bight towards the Western Australian coast. A trough continues
to lie off the west coast, with a weakening of the moist infeed from south of Indonesia to
the Australian continent. There is a
generally westerly movement of a broad area of convergence over the Coral Sea and near
Fiji which is pushing moisture onto the Queensland coast. The upper trough continues
to lie through the Tasman and into the Gulf of Carpentaria.
Discussion: The area of
higher pressure over Australia will remain over the eastern seaboard at around the 30°S
parallel during Saturday. The front will cross southeastern Australia behind a weak
prefrontal trough. The trough lying off the west coast will continue to edge southeast
towards the South West Land Division through the weekend. The infeed from the Indian
Ocean remains but has weakened substantially during the past day or so & is expected
to continue to weaken through the weekend. Patchy rain from this cloudband is likely
over the Central West and Gascoyne, extending into the Goldfields during Saturday but with
only light falls.
The high will locate over the entire southeast
later in the weekend with mainly fine conditions except for south of the ranges and over
the Alps in Victoria, the Alps in New South Wales and the west coast and highlands of
Tasmania, which will continue to experience scattered showers with some snowfalls down to
near 1100m during Saturday.
The trough through Queensland will move slowly east
during Saturday, but showers remain only likely along the exposed coasts
Areas to watch: The tropical
depression in the Philippine Sea for further development.
Rainfall potential
Victoria: Strengthening northwesterly-westerly winds. Showers in
the west, spreading east through Saturday, associated with a front moving across the
state. Showers in the south with possible hail & thunder near the coast,
particularly in the southwest. Showers developing over the Alps with snowfalls to
lower levels later Saturday. Isolated showers to follow in the southwest.
NSW: Increasing cloud with strengthening northwesterly-westerly winds through
Saturday. Isolated showers are possible with a prefrontal trough moving through the
east of the state, showers with and to the west of the front with snowfalls redeveloping
about the Alps, falling to near 1100m later in the day.
Queensland: Isolated showers about the top of Cape York and possibly
along the exposed northeast coast. Mainly fine elsewhere.
NT: Possible cloudy periods in the northeast with the chance of a light
shower. Fine elsewhere.
WA: Fine in the north. Showers through the central west and western
Pilbara and extending southeast through the Goldfields during Saturday. Only light
falls expected except near to the trough where heavier local falls are possible.
SA: Showers in the south and southeast clearing early Saturday to fine
conditions with only isolated showers along the exposed coasts. Remaining mainly cloudy
through much of the state.
Tasmania: Strengthening northwesterly-westerly winds reaching galeforce
at times, shifting west-southwesterly through Saturday. Widespread showers over the
west and north spreading east with snow falling over higher parts, to lower levels during
Saturday. |
19 |
. |
Overview: A high
located over southern New South Wales ridges to the west, while a low of 962hPa in the
southern Bight extends a trough (and front) to the northwest which bisects the baric ridge
across Western Australia to a low in the Indian Ocean at ~17°S. An upper trough is
located over the Tasman Sea and through western Queensland, with a thermal trough lying
just off the New South Wales coast. The front moving through the Bight is tightening
the pressure gradient southwest of the high over New South Wales resulting in a
strengthening of the northwesterly flow across the Bight and Tasmania. An upper ridge has
moved across South Australia and western Victoria during Thursday. An impressive cloudband across Western Australia and through
the Bight is associated with the subtropical jet but is showing signs of weakening as it
moves east. Ahead of this, warm temperatures have resulted from warm advection from
the northwest. Widespread rain (up to 30mm) over western and southwestern Western
Australia has been recorded during today from this cloudband.
Discussion: The surface high
over New South Wales will edge northeast while the front approaches southeastern Australia
during Friday. Strengthening northwesterly winds are likely over southern South Australia,
Victoria and Tasmania with increasing high cloud. The Southern Ocean lows will continue to
move through the south of the Bight near to 50 - 55°S with strengthening northwesterly
winds through the Bight at all levels. The cold pool in the southwestern Bight will remain
between 40 and 50°S as it moves east.
The baric ridge continues to lie across the
continent near to 30°S, but its influence over the west will continue to be eroded by the
trough extending northwest to the Indian Ocean and the cell to the west of Australia
remains only moderate in strength. This Indian Ocean trough is likely to remain in the
area for a few more days while its source of moisture remains to the south of Indonesia.
The area of cloud over northern Queensland is
likely to remain while the jet lies over the area and the trough over the Solomons &
New Caledonia slows the eastward movement of this jet over Queensland. An area of
cloud at lower levels over the northwest Gulf of Carpentaria appears to be feeding
moisture upwards and into this cloud streak. This area could prove worth studying over the
next day or two.
Areas to watch: An area of
convection over the Philippines should be monitored for signs of increased organisation
over the next day or so. The broad area of convection currently over the Solomon
Islands and New Caledonia is edging southwest into the Coral Sea.
Rainfall potential
Victoria: Strengthening northwest-westerly winds developing across the
state and becoming galeforce over higher parts. High cloud moving into the state.
Isolated showers developing over the Alps with the chance of sleet developing.
NSW: Conditions over much of the state will remain mainly fine after a cold
night. Strengthening northwesterly winds in the south, with isolated showers later in the
day over the Alps with possible sleet.
Queensland: Isolated showers along the tropical northeast coast and
about Cape York are possible
NT: Cloud over the northeast with possible showers in the area. Fine in the
south.
WA: Fine in the north. Patchy rain continuing over much of the southern
half of the state, extending east through Friday and then clearing in the southwest.
Some substantial totals are likely. Showers remaining about the west coast.
SA: Increasing high cloud from the southwest with strengthening northwesterly
winds & increasing temperatures. Only scattered showers are likely in the south later
in the day.
Tasmania: Strong northwesterly winds with turbulence in the lee of the
ranges. Showers developing in the west and extending east through Friday. |
18 |
. |
Overview: A high
pressure centre is located south of 30°S over South Australia near to the head of the
Bight. To its west, the upper jet associated with a longwave trough moving through the
Indian Ocean has captured the moisture plume spawned from the convective area in the
sub-tropics south of Indonesia, and is transporting it towards Western Australia. The
front that crossed southeastern Australia during Tuesday and Wednesday has moved off the
coast, while the jetstream can still be identified by the cloud patch over the
northeastern Queensland coast. A cluster of lows lies in the Southern Ocean between
40°S and 50°S (979, 975, 982, 995hPa at 10am AEST) with fronts extending to the
northwest to the trough in the Indian Ocean. To the west of this system, the thermal
trough extends as far north as 20°S!! Discussion:
The high will move eastward and strengthen during Thursday with a ridge to the west.
Northwesterly winds will strengthen along the South Australian and Tasmania west
coast and southwestern Victoria as the pressure gradient tightens with the eastward
movement of the front through the Bight. Increasing cloud crossing the west of Western
Australia will bring widespread rain areas to the coast and adjacent inland areas between
the Pilbara (later in the day in the north) and the SW Land Division. Ahead of this
trough, northwesterly winds and warm advection in the middle levels mixing down to the
surface will increase temperatures.
Isolated showers are once again likely about Cape
York & possibly near to or just north of the Top End coast with a weak trough
continuing to remain in the area during Thursday. Most of the northern parts of Australia
with the exception of these areas should remain fine. The trough moving through the
Tasman Sea towards New Zealand looks likely to deepen through the next day or so and, with
the intensification of a middle level cold pool, conditions look favourable for widespread
falls over the South Island, with some good falls of snow on the Alps.
Rainfall potential
Victoria: Isolated showers along the southwest coast, clearing through
Thursday. Mainly fine north of the ranges after local frosts and fogs. Some
drizzle over the higher parts of the Alps.
NSW: A cold night with some frosts over higher parts. Mainly fine
except in the southeast, where some early fog or drizzle is likely over the Alps in
particular.
Queensland: Mainly fine except about Cape York and the exposed eastern
coasts. Cool nights, mild days.
NT: Fine except for a possible isolated shower about the north coast, particularly
in the northeast.
WA: Remaining fine in the north. Increasing cloud in the south during
Wednesday night, and developing further north to the Pilbara on Thursday. Widespread
rain likely from this cloudband, with some heavy falls and thunderstorms possible, mainly
in the south. Warmer conditions ahead of the trough.
SA: Northwesterly winds strengthening in the west late in the day. Isolated
showers along the windward coasts, contracting to the southeast of the state and then
clearing through Thursday. Fine in the north with light winds.
Tasmania: Strengthening northwesterly winds in the west, showery, mainly
fine elsewhere. |
17 |
Clyve Herbert |
Nice long mid and upper cloud band just
off the West Australian coast. The long wave trough associated with this band seems to be
peaking at the moment, still it looks good there hasn't been this type of development in
that area for weeks. |
17 |
. |
Overview: The high
over Western Australia has become slow moving along the baric ridge which has moved south
to lie near to 33°S. A low of 970 hPa extends fronts to the north, affecting Tasmania and
Victoria during Tuesday with heavy showers, mainly south of the ranges in Victoria and
over western parts of Tasmania. Snow fell over the higher peaks. The next low in the
southern Bight (978hPa at 10am AEST) also has analysed warm and cold fronts, with the cold
front extending well north ahead of a thermal trough which extends into the subtropical
Indian Ocean. The warm front advancing through the Bight may remain far enough north
to affect Tasmania during Wednesday. A weak
trough remains over the Arafura Sea while a patch of high cloud over northeast Queensland
and back to the west coast to Broome identifies the location of the upper jet which
is bringing moisture across the continent from the Indian Ocean.
Discussion: The high over
Australia will remain slow moving and will continue to bring mainly fine conditions
to most of the continent during Wednesday as it moves toward the east coast. Fronts will
pass south of this high affecting southeastern Australia, while a front will approach
southwestern Western Australia later Wednesday / early Thursday. The front moving
across the southeast of the continent should move into the Tasman Sea during Wednesday
after affecting southern New South Wales and Victoria and bringing further snowfalls to
the Alps. Cooler air will become established over the southeastern states during
Tuesday and Wednesday.
A trough over the subtropical Indian Ocean looks to
deepen and extend to the southeast during Wednesday and Thursday, bringing some moisture
towards the Western Australian coast with showers likely to develop along the west coast
to the Pilbara later in the day.
Areas to watch: there is a buildup
of moisture to the southwest of Sumatra, with the subtropical jet becoming more meridional
in the Indian Ocean and reaching as far north as ~15°S. This area should be
monitored for moisture moving southeast towards Australia.
Rainfall potential
Victoria: Showers, mainly in southern and mountain areas, occasionally heavy,
mainly along the coast. Snowfalls redeveloping, with occasional heavy falls,
over the Alps and lowering overnight. Mainly fine north of the ranges during
Wednesday, showers scattered in the south.
NSW: Snowfalls redeveloping over the Alps during Tuesday night and into the
early part of Wednesday. Winds turning westerly in the south and strengthening. Turbulence
east of the ranges, particularly in the south Tuesday night and early Wednesday. Showers,
mainly along the ranges as the front crosses the state. Remaining fine in the north after
a cold night with frosts.
Queensland: Light showers along the central and northeast coasts are
likely while a weak upper trough over western Queensland should remain mostly inactive.
NT: Patchy high cloud crossing the state.
WA: Mainly fine in central areas with increasing cloud in the southwest and
west during Wednesday with showers developing likely Thursday as far north as the Pilbara
and extending inland. Northwesterly winds strengthening in the southwest.
SA: Isolated showers along the south coast with an onshore flow, becoming
fine during Wednesday.
Tasmania: Widespread showers in the western half of the state, with
snowfalls to lower levels Tuesday night and early Wednesday. Isolated storms.
Clearing Wednesday before the approach of another front. Westerly winds. |
16 |
. |
Overview: The baric
ridge lies near to 30°S and is beginning to edge slightly south again while a low in the
southern Bight (962hPa) extends a weakening cold front through the Bight to the South
Australian coast. A cold air field is identifiable in the Bight. The warm front preceding
this is moving southeast past Tasmania. The high over eastern Australia extends a ridge to
the southeast through New South Wales and into the Tasman Sea. A weak trough lies
over the northern Tasman not far off the east coast with scattered showers over northeast
New South Wales and southeast Queensland through Monday. An area of moisture over the
Indian Ocean to the southwest of Sumatra is beginning to edge to the southeast. Discussion: The eastern end of the
baric ridge across the continent will edge further to the south during Tuesday and the
weakening front will cross the southeastern corner, bringing scattered light showers and
snowfalls over higher parts, particularly in Tasmania. A moist southeasterly is
likely to bring scattered showers to Cape York. Elsewhere to the north of the baric ridge,
conditions will remain mainly fine with a southeast-easterly flow across the continent.
Some upper high cloud is likely to cross the West Australian coast over the west
Kimberley with the upper jet.
A satellite low will move through the Bight past
the southwest of Tasmania enhancing showery conditions over the southwest corner.
Colder air, which is associated with the upper trough, will move across the state during
Tuesday with highland snowfalls likely.
Areas to watch: there is a buildup
of moisture to the southwest of Sumatra, with the subtropical jet becoming more meridional
in the Indian Ocean and reaching as far north as ~15°S. This area should be
monitored for moisture moving southeast towards Australia.
Rainfall potential
Victoria: Scattered showers developing in the west, moving east and becoming
more isolated through Tuesday. Showers over the Alps falling as snow over the higher
peaks, with snow levels dropping later especially on exposed western slopes. Strengthening
northwesterly winds.
NSW: Isolated showers over the northeast coast Monday night clearing to a
fine day. A cold night inland with widespread frosts. Fine in the north. The front
moving through the south of the state should reach the coast later in the day with
scattered showers, falling as snow over the Alps to lower levels later, to follow in the
southwesterly flow.
Queensland: Isolated showers mainly over Cape York in a moist
southeasterly flow with a weak trough developing over the Gulf of Carpentaria. Mainly fine
elsewhere with cold nights in the south with frosts likely.
NT: Mainly fine. Cold nights in the south.
WA: Mainly fine throughout. Some high cloud over the western Kimberley.
Cool in the far southwest with only very isolated showers near the Capes.
SA: Showers over the southeast. Mainly fine elsewhere. Cold nights
inland.
Tasmania: Strengthening northwesterly winds Scattered showers becoming
widespread in the west with snowfalls reaching to lower levels during Tuesday, then
spreading throughout later in the day. Possible storms. |
15 |
Clyve Herbert |
The very large cloud mass south of your
area extends all the way to the west of Indonesia with some of the outflow slowly edging
southeast towards northwest Australia, with a bit of luck a good southern ocean low and
intensifying sub tropical jet may get some of this moisture onto the Australian mainland. |
15 |
. |
Overview: The baric
ridge lies near to 30°S with pressures ranging from 1015hPa in the north Tasman Sea to
1025hPa in the Indian Ocean. A trough is moving off the east coast of New South Wales and
has been responsible for isolated storms in the northeast of the state as well as
southeast Queensland during Sunday. A front extending from a Southern Ocean low (960hPa)
is crossing Tasmania and influencing southwestern Victoria during Monday evening. A warm
front extending from a 970hPa low at 45°S is moving southeast through the Bight, while
the cold front is crossing the southwest of Western Australia. This system is embedded in
an upper trough with the polar jet coming up towards our latitudes from the Southern
Ocean. Discussion: The
baric ridge will remain near to 30°S with a centre of high pressure over eastern
Australia extending a ridge to the southeast. Systems remain slow moving with the
low still located just east of New Zealand. The low in the western Bight, which is
associated with the upper trough, will deepen and move southeast during Monday, with the
cold front bringing showers to the southern Western Australian coast and strengthening
northwesterly winds along the South Australian and western Tasmanian coasts during Monday.
Some moisture is moving into the Timor and Arafura
Seas with a cross-equatorial surge, but generally, the area north of the baric ridge will
remain fine. Much of northeastern Australia has lacked in atmospheric moisture
during the past month or two with the more northerly location of the baric ridge allowing
moist southeasterly winds to penetrate across the coast over Cape York, while southwards
of this area, winds have tended more south - southwesterly. This has also seen colder
nights in the north than 'average'.
Areas to watch: there is a buildup
of moisture to the southwest of Sumatra, with the subtropical jet becoming more meridional
in the Indian Ocean and reaching as far north as ~15°S. This area should be
monitored for moisture moving southeast towards Australia.
Rainfall potential
Victoria: Isolated showers over the southwest coast Sunday night, clearing
through Monday and redeveloping later. Mainly fine north of the ranges with patchy frosts.
NSW: Southerly winds along the coast, and a trough just to the east will see
scattered showers along the central and northern coasts, clearing later Monday. A
cold night inland with scattered frost.
Queensland: Mainly fine except for isolated showers over the eastern
coast of Cape York. Cool nights with frost along the ranges.
NT: Mainly fine. Cold nights in the south.
WA: Mainly fine in the north. Some high cloud moving into the Pilbara.
Showers along the south coast, becoming more frequent with the passage of the front
Sunday night and then becoming isolated except in the far southwest.
SA: Early showers in the southeast, clearing. Scattered showers developing in
the west later Monday and moving east, mainly in the south. Strengthening winds ahead of
the front. Fine in the north with cold nights.
Tasmania: Showers during Sunday night, mainly in the west and north,
clearing early Monday before the passage of another front during Monday. Conditions
becoming colder Tuesday. |
14 |
. |
Overview: A
'dumbbell' of weak high pressure centres is aligned north-south through the western Tasman
Sea from near Brisbane to 40°S between the low near New Zealand and the approaching
trough currently moving through western Victoria. A front within this trough is
weakening as it slows its eastward movement with only widely scattered light showers being
recorded in South Australia and western Victoria during the day. An area of weak
vorticity is moving southeast from near to Mt Gambier to west of Tasmania. Much of southeastern Australia has experienced warm air in
the middle layers mixing down to the surface, with many locations recording above average
maxima. Most of the precipitation appeared to be virga. A trough extends northward from
this front into western Queensland. Cold nights were again widespread in New South Wales.
A low in the far southern Bight (960hPa at 10am
AEST) extends a warm front to the northeast through the Bight, closely followed by a cold
front just to its west. Another low and dual front combination is located to the west. A
ridge of high pressure is over Western Australia, once again near to 30°S, which has
weakened as it has moved east.
Discussion: The front, which
will continue to move slowly as its eastward passage is blocked, will cross Victoria,
western New South Wales and Tasmania during Saturday night / early Sunday, and will
have crossed the northeast New South Wales coast by Sunday night. Warmer air will move
across the southeast of the continent early in the new week following a cooling trend
during Sunday when snow showers about the Alps will redevelop. Showers are likely over
much of the southeast, extending into the northern parts of New South Wales behind the
front in a southwesterly flow. The trough (mainly inactive) over central Queensland will
move east during Sunday to be close to the coast by Sunday night.
The high pressure centre to the west will move
northeast into central parts of the continent, while the belt of low pressure will again
lie between 45 - 55°S and a series of fronts (including warm fronts), mainly weak, will
affect southern Australia for the next few days.
Rainfall potential
Victoria: Scattered showers in the west during Saturday night extending
eastwards with the passage of the front and then contracting south of the ranges and near
to the coast. Showers developing over the Alps, falling as snow at higher levels
initially, but to lower levels following the front. Isolated storms are possible,
mainly over Bass Strait Saturday night and early Sunday. Mainly fine in the north
with scattered frosts.
NSW: Showers, mainly in the south of the state, Saturday night, falling as
snow showers over the Alps, extending north and east with the passage of the front during
Sunday. Colder southwesterly winds to follow with scattered showers.
Queensland: Increasing cloud in the south with a shower or two possible.
Isolated showers over the far northeast tropical coast.
NT: Mostly fine.
WA: Mainly fine except for scattered showers over the far southwest, becoming
more frequent with the passage of fronts.
SA: Scattered showers in the south with possible hail near the coast Saturday
night will then redevelop later Sunday. Fine in the north.
Tasmania: Cool and showery Saturday night with possible hail and thunder
in the west. Clearing through Sunday briefly before showers redevelop later in the
day with the approach of another front. Possible snow showers on higher parts. |
13 |
Clyve Herbert |
The trough moving through Victoria is
slowing down a little, there seems to be weak vorticity near Mt Gambier at about 1430 hrs.
Another interesting cloud band is advancing across the Aus Bight which is a fairdinkum
'active warm front'. |
13 |
. |
Overview: A weak
high remains over northeastern New South Wales with a trough of low pressure through the
Bight extending from a low of 978hPa at ~ 42°S with a further pair of lows of 976hpa near
to 53°S. These surface lows are embedded within an upper trough (300hPa - 30,000'),
with a thermal trough at the 500hPa (~18,500') level located to its west and identifiable
by the cold air convection in the western Bight. The baric ridge over the Indian Ocean
remains rather weak and is located near 30°S. Colder air in the middle levels continues
to push north through Western Australia and is affecting latitudes as low as 25°S. Advection of warm and rather dry air in the mid levels
precedes the front moving through the Bight and this air mixing down to the surface is
resulting in a dry north - northwesterly flow.
A slow moving low remains over the New Zealand area
with moderate to heavy falls being experienced particularly in the North Island during
Friday.
Discussion: During Friday
night and Saturday, the front in the Bight will cross South Australia, Victoria and
Tasmania, with strengthening northwesterly winds with a brief warming trend ahead. The
passage of the front will bring colder, showery conditions to southeastern Australia
during Saturday, ahead of a ridge moving into our longitudes later in the weekend.
The baric ridge across the Australian continent
will continue to lie at near to 30°S with the trough moving through eastern Australia
dissecting it. The baric ridge will remain stronger over the west of the continent
and the Indian Ocean. Conditions to its north will remain mainly fine with only isolated
showers over the far northeast Queensland tropical coast expected. Cold nights in
New South Wales and Queensland are once again likely under the influence of the high -
record minima are possible again. Passing fronts will continue to affect the
southwestern corner of Western Australia during the weekend maintaining showery
conditions.
Rainfall potential
Victoria: Strengthening north-northwesterly winds in the west Friday night
ahead of the front moving into the west of the state on Saturday morning. Isolated storms
mainly in the southwest. Showers becoming more widespread with the passage of the
front, contracting to the south following the front. Showers over the Alps late in the
day, likely falling as snow to lower levels later Saturday / early Sunday.
NSW: Strengthening northwesterly winds in the south ahead of a front moving
through the south of the state during Saturday and reaching the coast on Sunday. Showers,
falling as snow over the Alps redeveloping later Saturday with falls to lower levels.
Mainly fine in the north after a cold night. Widespread heavy frosts over
many areas.
Queensland: Mainly fine except for isolated showers along the far
northeast tropical coast. Cool nights, mild days. Light winds.
NT: Mainly fine.
WA: Fine in the north and west. Cold conditions in the south with
scattered showers, more widespread in the southwest.
SA: Increasing cloud in the west with strengthening northwesterly winds ahead
of a front crossing the state Friday night / Saturday morning. Showers developing in the
west and spreading through the south of the state. Isolated storms in the south near
to and west of the front, with possible hail.
Tasmania: Increasing cloud through Saturday with strengthening
northwesterly winds. Showers developing in the west and north later spreading east.
Isolated storms. |
12 |
. |
Overview: The high
over New South Wales has continued to edge northeast and weaken through Thursday. A front
is currently moving through eastern South Australia and western Victoria with
strengthening northwesterly winds preceding it. Isolated storms are associated with this
front, and with the one to its west in the Bight associated with a developing wave low. The low in the Tasman is now analysed at all levels, has
deepened and become slow moving and is influencing the eastern Tasman Sea and New Zealand
with heavy rain particularly over the eastern parts of the North Island. The lows in
the Southern Ocean were 962 and 968hPa (10am AEST) and were lying between 55 and 60°S.
Discussion: The baric ridge
is again shifting north towards 30°S and the Southern Ocean lows are also moving slightly
north, re-establishing a general westerly flow over the southern Australian latitudes.
A broad longwave trough is located southwest of Western Australia with a strong
band of westerlies to its north and the polar jet making its appearance and extending to
the northeast on its western side.
The front moving through the southeast corner will
move into the Tasman Sea, while another front will cross Western Australia and much of
South Australia during Friday. Strong winds will continue and warm advection in the middle
layers will be experienced during Friday preceding this second front with some of this
warmer air mixing down towards the surface with low level turbulence.
Mainly fine north of the baric ridge with the
exception of the northeast tropical Queensland coast and the far northeast of the Top End.
Rainfall potential
Victoria: Showers, tending to light rain at times in the west with the
passage of a front Thursday night. Isolated storms in the south. Clearing through
Friday with winds restrengthening in the west later Friday ahead of the next front on
Saturday.
NSW: Strengthening northwesterly winds and increasing cloud ahead of an
approaching front. Fine in the central and north with light winds and cold nights,
with widespread frosts, especially over the ranges.
Queensland: Cold nights in the southeast with widespread fronts,
extending north along the ranges. Isolated showers in the northeast. Fine
elsewhere.
NT: Fine with the exception of isolated showers over the northeast of the Top End.
WA: Fine in the north. Widespread showers in the southwest and southern
parts, tending to rain periods during Thursday night, with southwesterly winds remaining
strong to gale force near the southern coast through Friday. Isolated storms in the south.
SA: Scattered showers and storms in the southeast Thursday night, clearing
through Friday with strong winds, strengthening again ahead of the next front later
Friday. Rain developing in the far west. Fine in the north after a cold night with frosts.
Tasmania: Widespread showers, particularly in the west and north,
tending to rain periods, and spreading east before clearing temporarily later Friday.
Conditions becoming cooler as a series of fronts moves across the state. |
11 |
. |
Overview: A slow moving
high is located over southern New South Wales near to 35°S with a mid-level thermal
trough located over the Tasman Sea, where a surface low is currently located, and to the
west, a tightening pressure gradient ahead of a front moving through the Bight. A
moderately deep low is located in the southern Bight (970hPa), while the other 2 centres
of low pressure in this 'family' are both 962hPa (10am AEST). To the southwest of
this front, is evident a large cold air field. The baric ridge is somewhat fractured across our longitudes by the
low in the Tasman and the front extending through Western Australia. A strong high lies to
the west of the continent near to 32°S. A continuation of the cross-equatorial flow from
Indonesia to the southeast across the Indian Ocean, continues to feed some moisture into
the trough preceding the front moving through Western Australia. Pronounced lee wave
cloud was located over Tasmania in the deep southwesterly flow.
Discussion: The upper
circulation over the Australian longitudes is becoming more 'meridional'. The high over
New South Wales will remain slow moving through Thursday, and is likely to be edged to the
northeast, with the deepening low moving towards New Zealand and the high ridging more
strongly to the southeast to cut it off. The steepening pressure gradient between
the high and the front to the west of the high will strengthen northwesterly winds over
South Australia during Thursday.
The cold air field southwest of Western Australia
is beginning to weaken a little as it moves northeast. A wave low developing on the
western side of the broad trough will move northeast also and affect the southwest of
Western Australia later on Thursday. The low pressure belt will remain around 50°S.
Definition: 'meridional' - the
north-south component of airflow is pronounced ie: the amplitude of the atmospheric waves
(ridges and troughs) increases.
Rainfall potential
Victoria: Strengthening northwesterly winds ahead of a trough and frontal
system. Increasing cloud with showers in the west, tending to periods of rain there
later. Remaining mainly fine north of the ranges.
NSW: Strengthening winds over the west with light winds over much of the
central and north of the state. Mainly fine throughout.
Queensland: Isolated showers over the northeast tropical coast. Fine
through the remainder of the state. Cool to cold nights in the south with frosts.
NT: Fine, with patchy cloud about the Top End coast. Isolated showers in the
northeast.
WA: Fine in the north. Showers in the south, with isolated storms in the
southwest, moving east and becoming more isolated through Thursday, but redeveloping in
the southwest later with a further strengthening of the winds.
SA: Increasing cloud in the southwest with strengthening northwesterly winds.
Isolated showers in the south becoming scattered with the passage of the front,
Coastal showers remaining in the following moist onshore flow.
Tasmania: Strengthening northwesterly winds with increasing shower
activity particularly in the west and north later Thursday. |
10 |
. |
Overview: The baric
ridge remains near to 30°S with a relatively weak centre in the north of the Bight. A
wave low moved across Tasmania today with a series of fronts crossing Victoria bringing
isolated hail in the south and snowfalls in the Alps. Strong to gale force southwesterly
winds followed the fronts. Low pressure systems of 966 and 973hPa are located between 45°
and 50°S south of the Bight. An extensive cold air field lies to the southwest of Western
Australia. Discussion:
The high over the north of the Bight on Monday will continue to move east through New
South Wales during Wednesday. The upper trough to the west of the Australian continent
looks to deepen, with the cold airfield in the middle layers associated with it continuing
to move towards the northeast. A wave low is likely to form in the western Bight, but is
likely to slide southeast.
The front currently moving through New South Wales
is drawing some of its moisture from a cross - equatorial surge from Indonesia into the
Indian Ocean. A cooler west-southwesterly surface flow will follow these fronts and
isolated showers over exposed parts of the eastern ranges of Victoria and New South
Wales as well as the southern the New South Wales coast are likely to persist.
Western Tasmania will see a continuation of showery conditions.
The family of lows in the Tasman Sea will influence
New Zealand during Wednesday.
Areas to monitor: The convective
area near to the Solomon Islands has weakened substantially after being sheared to the
southeast, but is still apparent in the area (a low-latitude TC like Vamei within 5° of
the equator is a remote possibility).
Rainfall potential
Victoria: Scattered showers becoming isolated and contracting to the east.
Isolated showers, falling as snow of the higher peaks. Winds moderating through the
day. Mainly fine north of the ranges after a cold night.
NSW: Cooler conditions will become established over the south of the state,
with isolated showers on the exposed peaks, with only isolated show showers. Cold with
frosts, some possibly severe in the north.
Queensland: Mainly fine except for isolated showers along the northeast
coast. A cool night, especially in the south and along the ranges.
NT: Mainly fine with only isolated showers about the northeast coast. A possible
congesting cumulus.
WA: Fine in the north of the state with scattered showers in the southwest
and south becoming more widespread with the approach of a stronger front. Strengthening
northwesterly winds ahead of the front, possible storms with hail with and following the
front.
SA: Mainly fine. Fogs in the southeast & frosts likely inland,
particularly in the northeast of the state. Strengthening northwesterly winds in the west
later.
Tasmania: Showers in the west, south and north Tuesday night and during
the early part of Wednesday with isolated light snowfalls over higher peaks, clearing,
showers only scattered in the east. |
9 |
. |
Overview: The highs
centred near to 30°S over eastern Australian on the Indian Ocean, have weakened through
Monday. Deep lows in the Southern Ocean (959 and 969hPa at 10amAEST) extend their
influence north with a wave low having developed southwest of Tasmania and a pair of
fronts, one which has had its middle section dragged east by the jet, faster than its
northern and southern extremities. The front is marked as stationary through Bass
Strait, and the trough extending to its northwest can be traced into the Indian Ocean
subtropics south of Indonesia. A series of
troughs and fronts is embedded in a zonal westerly flow through the Bight.
Discussion: The troughs and
fronts within the zonal westerly flow which is currently affecting a large part of
southern Australia, particularly in the central and eastern regions, will move east and
affect us during the next day or two. The baric ridge will likely maintain its approximate
position near to 30°S to the north of this area and remain relatively weak, while the
Southern Ocean lows to the south will continue to locate further north than is 'usual,
with a resultant strengthening of the winds between these two areas.
A series of fronts will cross the southeast of the
country during the week, triggering widespread showers throughout, falling as snow at
higher levels.
Definition: 'zonal' wind / flow
tends to lie closely aligned to parallels of latitude ie: the west-east component of
motion is most pronounced.
Rainfall potential
Victoria: Strengthening northwesterly winds, reaching gale force at time in
southern and mountain areas, turning west - southwesterly later. Showers in the southwest,
becoming more frequent through Tuesday and spreading east with the passage of
fronts.Isolated snowfalls over the peaks. Chance of a storm in the south. Mainly
fine north of the ranges.
NSW: A strengthening west - northwesterly flow ahead of a front moving
through the south. Showers with and behind the front, falling as snow over the
higher peaks. Lighter winds and mainly fine in the north.
Queensland: Mainly fine but with isolated showers over the northeast
coast. Cool in the south with cold nights inland with frosts.
NT: Fine except for isolated showers in the northeast of the Top End.
WA: Fine in the north. Scattered showers in the southwest, becoming
more frequent later in the day.
SA: Scattered showers over exposed coasts of the southeast, becoming more
widespread with the passage of the front. Mainly fine elsewhere. Cold nights
inland with frosts.
Tasmania: Widespread showers, tending to periods of rain in the west and
north with isolated storms and hail. Snowfalls on the higher peaks likely later.
Northwesterly winds strengthening to gale force. |
8 |
. |
Overview: The high over
South Australia has weakened slightly and moved east during Sunday to be in northwest New
South Wales while remaining at ~30°S. A tightening pressure gradient between this high
and the approaching low and front to its southwest is strengthening the northwesterly flow
over coastal South Australia and the eastern Bight. The area of convection that was
near to the Solomons on Saturday, has been caught up in the southeasterly upper flow and
has moved north of the North Island of New Zealand. The interaction o the surface
low together with the thermal trough over the eastern Tasman Sea, leads to the likelihood
of the North Island of New Zealand expecting heavy rain late Sunday and into Monday. The lows (956 and 959hPa) in the Southern Ocean low pressure
belt are currently located between 50°S and 55°S. A series of fronts is moving through
the Bight and a deep northwest-southwesterly flow continues to dominate the southern part
of Australia.
Discussion: The high over
eastern Australia will continue to move east through Monday with the first front crossing
the southeast of the continent. A weak wave low is likely to develop southwest of Tasmania
and move southeast. The next high will move in from the Indian Ocean, with the baric ridge
maintaining its position at ~30°S. The deep northwest - southwesterly flow will
continue to dominate southern Australia through Monday.
Northwesterly winds will strengthen through Monday
over the southeast corner ahead of the approaching front. Showers will become more
frequent particularly near to the southwest coast and along the ranges of Victoria while
the west coast and Bass Strait coast of Tasmania being favoured. The southwest corner of
Western Australia is likely to see a continuing of isolated showers in the onshore flow.
Conditions to the north of the baric ridge will
remain mostly fine.
Rainfall potential
Victoria: The front looks to weaken as it moves east and only scattered
showers are likely with isolated snowfalls over the peaks later. Northwesterly winds to
strengthen to gale force at times, especially along the coast and the Alpine district.
NSW: Fine in the north. Scattered frosts likely. Scattered showers
developing in the south later Monday / Tuesday, falling as snow over the higher peaks.
Queensland: Mainly fine with frosts in the south and possibly extending
to the central highlands.
NT: Fine throughout.
WA: Fine in the north. Scattered showers over the southwest, continuing
but becoming less frequent through Monday.
SA: Scattered showers and strengthening northwesterly winds with the passage
of the front. Coastal showers to follow in the onshore flow. Fine in the north.
Tasmania: Scattered showers, tending to periods of rain, mainly in the
west and along the Bass Strait coast. Strengthening northwesterly winds. |
7 |
. |
Overview: A high is
located near to 30°S over South Australia and influences much of Australia's weather. A
small wave (satellite) low, that developed on the western side of the broad area of low
pressure last night in the southeastern Bight, moved northeast Friday night along a steep
pressure gradient and then east through Bass Strait during Saturday, bringing widespread
showers, some heavy, and strengthening the winds to strong to gale force along the
Victorian coast and into southeastern New South Wales. Strong westerly winds were one catalyst for some good snowfalls over
the exposed resorts (~12cm at Mt Hotham) during Saturday, with even light falls reaching
the Central Tablelands of New South Wales.
A string of lows within the Southern Ocean low
pressure belt extends from the South Island of New Zealand to the southwest of Western
Australia - this belt is rather further north than 'usual'. An area of convection is
located over the Solomon Islands, mirroring an area in the northern hemisphere, and is
moving steadily southwest. A front is approaching the southwest of Western
Australia.
Discussion: During Sunday,
the high will maintain its strength and move slowly east along the baric ridge which is
currently just to the north of 30°S. Winds to the north of the baric ridge will remain
light with mainly fine conditions continuing over the northern half of the continent
except for the far north of Cape York and the northeast of the Top End which may see an
isolated shower. Winds over southern Australia will moderate briefly during Sunday as the
high moves to our north, before restrengthening as the next low approaches the southeast
early in the week.
The low to the south of the front crossing Western
Australia during Sunday will slide southeast through the Bight, but to its west is a large
cold airfield associated with a deep (as well as broad) long wave trough, which will move
steadily towards the Australian continent.
Rainfall potential
Victoria: Isolated showers, mainly on and south of the ranges, particularly
in the far east, falling as snow over the Alps. A cold night in the north with local
frosts. Westerly winds moderating through Sunday. Cool.
NSW: Isolated showers over the Alps falling as snow at higher levels.A
west-southwesterly flow over the east of the state, with cool conditions - winds
moderating through Sunday.
Queensland: Isolated showers over the north of Cape York, particularly
on the east coast, mainly fine elsewhere.
NT: Fine except for an isolated shower over the northeast of the Top End.
Cold nights ion the south with widespread frost.
WA: Showers, becoming widespread in the southwest and along the west coast
with isolated storms with the risk of hail, associated with the passage of the front
through Saturday night / Sunday. Showers extending along the south coast through the day,
and remaining scattered in the southwest. Fine in the north.
SA: Fine in the north with frosts. Isolated showers developing along
the south coast, while showers will remain scattered over the exposed parts of the
southeast corner for the rest of the weekend.
Tasmania: Showery in the west and south, clearing to the east during
Sunday. Showers, falling as snow at higher levels on Saturday night, with the risk
of storms, clearing through Sunday. Winds moderating before restrengthening later in the
day ahead of the next front. |
6 |
Clyve Herbert (Leopold, Vic) REPORT |
With the passage of a small wave low
through Bass Strait this morning this left my location (Leopold) open to 6 hours of solid
65 to 75kph sustained winds and gusts to 88kph, although the peak gusts were not unusual
the long period of sustained high averages was unusual. In respect to the Illawarra I
suspect a pretty decent lee wave set-up over your region and would not be surprised if
some of the subsiding air may have come from the mid or upper layers. After the passage of
the trough this morning (possible warm front) the lower atmosphere was filled with a milky
haze that reduced visibility sufficiently to take most of the blue out of the sky I
suspect salt haze to be the culprit. |
6 |
Laurier Williams (Blue Mountains, NSW) REPORT |
I've just done the preliminary national
weather extremes for today (go to http://www.australianweathernews.com/news/news.html,
click today's date and go to the bottom of the page) and there are some pretty impressive
figures. In the Illawarra, Albion Park hit 100, but also Bellambi scored 96, Nowra and
Montague Island 93 and Kiama 91.
Interestingly, the wind here at Blackheath has been pretty moderate today. A lot of high
figures in Victoria, with Wilsons Prom's 130km/h just after noon with an average of 93
being the standout, and the Kingfish oilrig in open water off Sale recording a gust of
102km/h at 2.20pm. Don't think I'd like to be in a small boat in Bass Strait today.
Melbourne Airport scored a top *mean* windspeed of 72 and Sydney Airport 63 during the
day. |
6 |
Gavin O'Brien (Canberra) REPORT |
After a quiet morning, we have had strong
Northwest winds with gusts to 75 km/hr in past hour with a peak gust of 80 km/hr
from West North west recorded at Gilmore at 14 30 (2.30 pm). Only damage I have seen
was the neighbour's garage roller door has been blown in, plenty of leaves ,twiggs
ripped of trees.Seems a strong Fhon effect and strong down drafts coming off the
Brindabellas accross the valley. Cloud capped by Inversion about twice the height of the
Range (ie about 3300 metres ASL) |
6 |
Michael Thompson (Wollongong, NSW) REPORT |
As hard as it is to believe the winds
have actually got stronger this afternoon in the Illawarra. Gusts are now ripping spray
from the surface of Lake Illawarra, in my rough experience it takes over 45 knots for this
happen. We now have had near two days of non stop gale force winds. At 16:30 according to
Laurier's AWS page for the Illawarra Albion Park hit a
100kmh gust. That 100kph gust has now been followed by a 106kph at 17:45. |
6 |
Chas Osborn (Strachan, Tas) REPORT |
Our surface temperature increased with
the passage of the trough line (frontal line?) in the early hours of this morning.
Temp pressure
01:00 NNE 7 /10 5.3
994.0
02:00 NNE 8 /11 5.6
993.7
02:44 W 18 /28 8.4
993.5
03:00 W 17 /26 8.1
993.9
03:02 W 17 /27 8.2
993.9
04:00 WSW 15 /23 8.2
994.4 |
6 |
Andrew McDonald (Melbourne) REPORT |
Thoughts - the warming is possibly due to
the cold air moving away to the east. Its a fair distance from Melbourne to Mt
Gambier so it is feasible that the atmosphere is stabilizing W of Melbourne.
Interestingly enough....that front went through Wilson's Prom between 11am and 12pm and
now Wilsons Prom has gusts to 70knts (130km/h) with sustained winds of 50knts (90km/h). |
6 |
Jane ONeill (Melbourne) REPORT |
I've checked the soundings and it looks
like the trough moving through Victoria associated with the wave low that passed through
Bass Strait this morning may be another weak warm front.
The soundings for Melbourne & Mt Gambier show a warming trend behind the trough....
as at 0Z (10am) this morning:
Melbourne
850hPa 0.6 700hPa -8.7
500hPa -27.3 400hPa
-40.9
Mt Gambier
850hPa 1.8 700hPa -7.1
500hPa -25.7 400hPa
-39.1Thoughts? |
6 |
. |
Overview: The baric
ridge across Australia extends from Perth to Brisbane, and is located further northward in
its eastern extremity due to a combination of a complex area of low pressure currently to
the southeast and south of the continent at the surface, as well as the
configuration of the upper jet. An upper trough and surface front, connected to this
complex low south/southwest of Tasmania, lie aligned almost west-east across New
South Wales and into central South Australia and are moving steadily northeast. The
jet core over Victoria has transported the central part of the front to the east faster
than its northern and southern extremities. The
airmass following the front is considerably colder, especially in the middle levels. A
deep westerly flow is established behind the front with satellite lows forming west of the
major centre and moving east, and this entire area is part of the broad thermal trough in
the middle levels which extends over Tasmania and the entire Bight.
Conditions in the northern half of Australia north
of the baric ridge remained mainly fine during Friday.
Discussion: During Saturday,
the high over Western Australia will move northeast to lie over South Australia, while
cloud moving into Western Australia near to 30°S marks the location of a strengthening
upper jet. The front will move through New South Wales and southern Queensland through
Saturday. The thermal trough will move across much southeastern Australia during Saturday
with an upper ridge moving in behind it later in the weekend, bringing less extreme
conditions for a brief interlude before the next series of fronts early in the week.
Conditions north of the baric ridge should remain
mainly fine, with isolated showers along the Queensland coast a only slight risk during
Saturday.
Rainfall potential
Victoria: Scattered showers, mainly on and south of the ranges, falling as
snow at higher levels, particularly on Friday night and the early part of Saturday.
Isolated storms and hail are possible, mainly in the south.
NSW: Rain periods ahead of the front, with winds tending westerly with
showers to follow, falling as snow at higher level Friday night and early Saturday,
becoming more isolated during the day. Possible light snow extending briefly as far
north as the Central Tablelands.
Queensland: Mainly fine except for isolated showers over the far north
of Cape York. Cold nights over mush of the state with widespread frost.
NT: Mainly fine. Nights becoming colder in the south.
WA: Isolated showers over the southwest corner. Increasing high cloud over
the lower southwest with showers becoming more general for a period. Fine elsewhere.
SA: Mainly fine except for scattered showers over the southeast corner, and
only isolated showers over the northeast. Isolated storms with hail in the southeast
Friday night and early Saturday are possible.
Tasmania: Remaining showery, mainly in the west and south, with snow to
low levels on Friday night . Isolated storms with hail are also likely. |
5 |
. |
Overview: The passage of
a warm front, courtesy of a deep low in the Southern Ocean (939hPa 10am AEST), across
Victoria today resulted in a period of rain and milder temperatures following the front,
both at the surface and in the upper levels. A broad and complex trough lies over the
Tasman Sea with a thermal trough to its west. The baric ridge has shifted north to lie near to 25°S across the
continent, while the broad westerly flow continues to influence southern Australia to the
south of the high pressure region. A series of fast moving fronts is embedded in this
flow. A wave low is located in the southern Bight southwest of Tasmania. An area of
convection north of the Solomon Islands is mirroring a similar area of convection in the
northern hemisphere almost due north.
Discussion: The
strengthening upper jet over the northern Bight and South Australia will speed the
'middle' part of the front eastward faster than its northern or southern extremities, with
South Australia, Victoria and Tasmania feeling the effects of the front during Friday. The
satellite low in the eastern Bight, which may deepen during Friday, is likely to move
northeastward around the broad trough, strengthening southwesterly winds and enhancing
showery conditions for Tasmania.
The ridge of high pressure crossing the continent
is likely to edge slightly south following the passage of the front and strengthen in the
west, with showery conditions along much of the south coast of Western Australia,
clearing as the high begins to dominate the area. The coldest air in the mid levels will
continue to influence the southeast of the continent during the next few days, with
widespread showers developing and sometimes heavy snowfalls at higher levels.
Remaining mainly fine over the northern half of the
continent north of ~30°S.
Rainfall potential
Victoria: Strengthening west-southwesterly winds Thursday night and early
Friday ahead of a cold front moving through the state during Friday. Widespread
showers developing ahead of and with the front, with the chance of hail in the south.
Snowfalls, becoming more frequent later in the day at higher levels.
NSW: Cool to cold conditions with a strengthening westerly wind throughout
the south of the state. Scattered showers, falling as snow over the Alps and higher parts
of the Tablelands, possibly extending to the Central Tablelands at times.
Queensland: Mainly fine except for isolated showers over the northern
part of Cape York.
NT: Mainly fine.
WA: Fine in the north. Scattered showers in the southwest becoming more
frequent with the passage of a front along the southern coast. Showers clearing
through the day.
SA: Showery conditions along the Eyre Peninsula and to the southeast, with
heavier falls over the southeastern corner, and becoming more frequent with the passage of
a front during Friday. Chance of hail in the southeast. Colder conditions to
follow.
Tasmania: Widespread showers in the west and south, with snow over
higher peaks later Friday. Strengthening westerly winds likely to reach gale force
at times. Isolated showers in the east. |
4 |
. |
Overview: The baric
ridge across Australia has been pushed northward during Wednesday and has been interrupted
over eastern Australia with the westerly flow extending north with a trough and front
embedded in the flow at the surface, and a thermal trough in the middle levels. Cold air
is evident over the southeast of the continent extending to near the Queensland border.
The baric ridge is located slightly southward as it passes over Western Australia, but
remains north of 30°S. A complex of lows is
passing through the southern Bight (983 and 985 hPa) with a satellite low on the western
side of the upper trough moving to the northeast towards Tasmania. A broad upper
trough lies to the southwest of Western Australia with a surface low of 934hPa south of
Western Australia near to 60°S - this is getting close to a record!!
Discussion: During Thursday,
the high over Western Australia will move steadily east, keeping to its well northerly
track. Fronts will cross southern Australia in the westerly flow which remains strongly
established. Western Australia will be affected by a front crossing the southwest, with
showery conditions to follow, becoming colder. Showery conditions, with possible hail and
highland snow, extending down to lower levels, particularly behind fronts, look to be
widespread for southeastern Australia during Thursday, including as far north as the
central New South Wales ranges.
Rainfall potential
Victoria: Widespread showers during Wednesday night. Showers along the
ranges, falling as snow at lower levels with the passage of a series of fronts.
Possible storms with hail during Wednesday night, mainly south of the ranges. A
northwest flow shifting southwesterly. Cold.
NSW: Showers, falling as snow at higher levels, with possible light falls
reaching the Central Tablelands at times. Strengthening west-southwesterly winds
with heaviest showers along the windward slopes of the Divide.
Queensland: Scattered showers along the northeast tropical coast.
Fine in the central and northwest. Becoming colder in the south with local
frosts.
NT: Fine with the risk of isolated showers in the northeast corner. Cold
nights in the south with locally severe frosts likely in some areas.
WA: Fine in the north. Isolated showers becoming more frequent with the
passage of a front, extending along the south coast, with colder conditions developing.
SA: Showers, mainly in the south, becoming more frequent at times.
Tasmania: Showers, mainly in the western half of the state and the
northern coast. Strong westerly winds. Highland snowfalls are likely in the
west and south. Only isolated showers in the east. |
3 |
. |
Overview: The high has
weakened to the east and been absorbed into the baric ridge over southern Queensland,
while the ridge has strengthened westward over the Indian Ocean. A front is crossing
Victoria and Tasmania late Monday while a wave low at ~38°S is apparent over the Bight
near Esperance. A pair of deep lows is passing to the south of the Bight (982 and 973hPa).
The cold air field over the Bight is showing widespread and frequent showers with
gales expected to develop. Discussion:
The baric ridge will remain north of 30°S and its eastern end will continue to weaken,
while the centre moving over Western Australia will also weaken as it moves east. The lows
in the Bight, including the wave low near Esperance will move southeast, while another
wave low looks a possibility to develop in the trough near to the west of Bass Strait
during Wednesday. Strengthening northwesterly winds ahead of the front will see slightly
milder conditions for a brief period before the front with a shift to a west-southwesterly
flow to follow.
Conditions will remain clear over much of the
continent with cold nights continuing and light winds north of the baric ridge.
Rainfall potential
Victoria: Isolated storms in the southwest near the coast and over Bass
Strait during Tuesday night. Strengthening northwesterly winds shifting to westerly
through Wednesday across the state, with showers developing mainly south of the ranges,
falling as snow over the Alps. Chance of storms, particularly in the south and
along the ranges.
NSW: Showers developing in the south falling as snow at higher levels.
Colder west-southwesterly winds extending into central parts of the state behind the
front, with showers, particularly along the ranges.
Queensland: Isolated showers over the northern part of Cape York and the
northeast tropics. Colder nights in the southeast with local frosts. Light southwesterly
winds throughout the south.
NT: Cloudy periods in the northeast. Fine elsewhere, cold in the south with
local frosts.
WA: Scattered showers remaining in the southwest corner and possible
extending along the south coast, fine elsewhere.
SA: Scattered showers mainly in the southeast, with showers along the south
coast also in a moist unstable southwesterly flow. Fine with cold nights inland.
Tasmania: Showery conditions in the west, becoming widespread through
Wednesday. Early fogs in the east, clearing before showers develop later in the day.
Possible snow on higher peaks with the chance of thunder. |
2 |
. |
Overview: A weakening
high remains over the eastern part of the continent ridging to the south through the
eastern Bight as part of the baric ridge near to 30°S. A complex pair of lows (982
& 976hPa) with a front that extends northward is moving through the central Bight,
strengthening winds during Monday along the southern West Australian coast.
Widespread showers across the southwest of the state follow this front, with cooler air
extending north to near Geraldton. Discussion:
Temperatures Monday night are likely to be milder under lingering cloud cover over much of
Victoria. A cold night over New South Wales and southern Queensland extending across
the continent under clear skies. During Tuesday, the baric ridge will begin to shift
slowly northward and slowly weaken. The low in the Bight will continue to deepen but slide
southeast, as the southward ridge from the high moves east into the Tasman Sea. The front
extending north through the Bight will affect South Australia during early Tuesday, and
Victoria and Tasmania later in the day. Weak tropical infeed is still traceable to
this area. Behind the front, the westerly flow begins to set up through the Bight.
Isolated showers are again likely along the
tropical Queensland coast in an onshore southeasterly flow.
Rainfall potential
Victoria: A mild night south of the ranges with isolated showers along
the coast, cold conditions to the north with frosts. Northwest winds with increasing
cloud and showers developing, falling as snow at higher levels.
NSW: Morning frosts with a fine day to follow with strengthening northwest
winds. Increasing cloud in the south with showers developing, falling as snow over
the Alps later.
Queensland: Isolated showers over the northern tropical coast and Cape
York. Fine elsewhere with widespread frost in the south.
NT: Cold nights in the south. Fine throughout, with the chance of cloud over
the northeast of the Top End.
WA: Fine in the north. Scattered showers in the southwest, extending
east during Monday night and into Tuesday.
SA: Showers, isolated in the south and central parts becoming scattered with
the passage of the front during Tuesday. Remaining fine in the far north of the state.
Tasmania: A cold night with fogs likely. Strengthening northwest wind,
with increasing cloud and showers, mainly in the west and north, becoming more widespread
during Tuesday. |
1 |
. |
Overview: The high has
weakened slightly but is planted firmly over eastern Australia and shows strong upper
level support. A weakening front is crossing the southeastern states, while sliding
southeast at the same time. The infeed into this system from the Indian Ocean has weakened
right out over the past 24 hours. Another front with a stronger thermal trough
following is approaching southwest Western Australia. A strong high follows from the
central Indian Ocean. A deep low and associated cold pool is approaching New Zealand. Discussion: The high will remain slow
moving through the next day or so edging to the east-northeast, leading to very cold
nights over the much of the eastern states, with severe frosts in some areas, particularly
away from the coast and along the ranges. Conditions may be somewhat moderate under
any lingering areas of cloud following the weak front through Victoria and Tasmania. Days
will be cool with light winds, and fogs may linger to mid-morning in some areas.
An upper level feed of moisture from the tropical
Indian Ocean into a prefrontal trough precedes the front crossing Western Australia, which
may strengthen during Monday as the upper jet strengthens.
Rainfall potential
Victoria: Isolated showers, mainly in the south. Widespread
frosts, especially north of the ranges. Temperatures will be more moderate under
areas of cloud lingering behind the weak front crossing the state. Fine otherwise.
NSW: Cool to cold conditions, particularly in the south. Widespread frosts,
particularly along the ranges and away from the coast - may be severe at some locations.
Light winds except over the south coast. Fogs along the ranges, possibly clearing
late.
Queensland: Only isolated showers in the far northeast. Cold in
the south with scattered frosts, mainly in the southeast, but possibly extending north
along the divide. Fine conditions with light winds.
NT: Fine with the chance of cloud in the northeast. Cold in the south
with scattered frosts.
WA: Showers in the southwest associated with a prefrontal trough, with
isolated storms and possible hail following the passage of the front. Fine
elsewhere.
SA: Light showers Sunday night associated with the front crossing the
southeast of the state. Mostly fine elsewhere after a cold night with widespread frosts
and scattered fogs, mainly in the central and north.
Tasmania: Showers Sunday night in the west and south, becoming more
isolated during Monday. Cold nights with frosts and scattered areas of fog to the
east. |
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June Forecast Outlook, Discussion
& Report page |
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Victorian Weather Glass |