Re March 1 thunderstorm/supercell event for pre TC George.
Finally got some info from contact at the Met office here re the deepening low that passed us by this day. I'll copy type it word for word. Some interesting comments to say the least! Thanks to Greg Browning at the Severe Weather Section, Darwin Met Office.
"Ive also had a quick revisit of the !st March event and the later sounding shows no appreciable difference to the morning trace, if anything there is a bit more warming at 11Z.
The morning's sounding though gave an indication for all the ingredients needed to generate the kind of storms that could produce that amount of lighting you witnessed (and I enjoyed!). Analysis yielded CAPE over 4000j/kg, LI of -6.9C, mid/low Level shear (1000 to 10,000ft) of 147/67, steering wind of 40+ knots etc. As one Paul Keating would have said...those are beautiful numbers!
On top of this the main line of storms came through that night was associated with the outer convective rainbands of pre TC George and so extra vorticity and convergence also added to the mix, recall this was the environment that produced the high F2 tornado in Kakadu NP.
The sounding also showed some low level dry are due to sub-FZL evaporation of the considerablerain falling at thetime - which likely contributed to some explosive updrafts after the LL environment was eventually modified to the requisite degree.
So you had major instability contributing to the explosive updrafts along a favoured convergence line, shear and steering winds conductive to extensive and continued propagation along a wide swath and for a significant period of time. There were numerous strong cells embedded in the main rainband and their conmined effect was the almost continuous lightning that you saw."
I also commented to him that thankfully I have been studying the last 6 months and knew what he was talking about, phew!
Mike
