Saturday 3rd August 2002 was going to be a good day! The upper trough over
southeastern Australia was amplifying with both an upper low located near Kangaroo Island
and a surface low likely to develop near Mt Gambier. I spent the Saturday morning
pottering about and keeping an eye on conditions while waiting for the 12.30pm updated
satellite image - I already knew I was going north, but wanted to confirm the situation
before I left (the last satpic had been 9.30am). The satpic showed that the upper low had
moved into southern New South Wales, there was a complex trough over Victoria and a look
out the window to the southwest showed some interesting development. Out the door at
1.15pm.....
Managed to get a full 3 kms
from home, stopped to get petrol and spent the next 20 minutes monitoring (and
photographing) a convergence line moving across the eastern suburbs of Melbourne complete
with suspicious ragged lowerings. These certainly piqued my interest, and I wondered what
conditions might be like in the northeast of the state, closer to the upper low and ahead
of the weak trough I had just photographed. I began to see congesting cumulus near Seymour
as I headed north, and I monitored the development of a multicell that I picked up west of
Seymour as it tracked northeast - conveniently parallelling the highway. Stopped to take a
few photos and noticed ragged lowerings which looked suspiciously funnel - like, but this
storm was too far away at that time to be able to see detail clearly. An intercept
with this cell looked possible, so I continued northeast keeping one eye on this cell to
my left (west) and watching another smaller developing cell to my right (east).
Just south of the Euroa turnoff came
the "there's a cell on my left and a cell on my right.....and I'm in between
them...which way to go???" 5 second decision making game...I turned off the highway
towards Euroa, glanced to my right, dragged the steering wheel to the left with one hand
while digging digital camera & video out & turning them on...I stopped the car,
was across the road (dodging people riding past on horseback) to get a better view of a
funnel starting to form from the cell to the east of the highway....a significant funnel
extending about 20% to the ground developed within a minute or so. A few digital images
were taken and some shaky video while the funnel began to weaken, but it never quite
dissipated. I shot back across the road to get the tripod - and couldn't find the
fitting for the bottom of the video.....so back across the road to spend the next 9
minutes taking photos, video and watching the development of not just a funnel, but a weak
tornado.
The duty forecaster at the Bureau of
Meteorology in Melbourne that afternoon certainly wasn't expecting my phonecall reporting
what appeared to be the development of a significant funnel near Euroa, let alone having a
storm spotter shouting in his ear with excitement as a condensation funnel developed all
the way down to behind the trees 3 kms away while I watched and videoed!! He asked
if the cell had any lightning - I said "no" seconds before lightning exited
above the wallcloud and re-entered the cloud just below!! What had appeared on radar
at that point to be a congesting cumulus on the southwestern edge of a retreating area of
moderate instability had just dropped a funnel / tornado as well as lightning!!
I captured 9 minutes of video from the
very beginning of the development of the funnel, through the development of the
condensation funnel - the funnel and tornado lasted more than 14 minutes before
dissipating slowly to the east of a heavy rain area, lifting from the ground and trailing
off to the northeast, while still extending at least half way between the cloud and the
ground. Any effects from a circulation on the ground was well away from the road
network and across open paddocks - I am not aware of any structural damage reported, but I
doubt that damage consisting of broken branches or ploughed up back paddocks would be
reported to the authorities. |