Pictures without time / date can be clicked on for a larger image - thanks to Jane O'Neill for supply of some digital images Day
5, 29th November 2000 - Gunnedah to Gunnedah, 250kms, Severe storms
widespread throughout eastern New South Wales. We encountered a severe
multicell near Gunnedah. AN
EARLY START With the chasers in three groups our smaller team stuck to the Quirindi storm. After about an hour it had indeed weakened, but its outflow boundary had penetrated into the hot plains air ( 32C ) lifting it and fresh activity was rapidly growing on the northern flank of the old storm. Over the next 6 hours we followed this erratic outflow line, as cell after cell pulsed then died only to be replaced by another just a little further north. Anvil thunder was almost constant, surprising for such small storms.
Over the next 90 minutes the storm persisted east of us and pulsed several more microbursts. We headed back to town with the intent of calling it a day, but decided on one last look on the outskirts of town. Electrical activity had now picked up, so we settled down to watching the lightning show until 9.30pm when finally we driven indoors by a small cell developing over our heads. A great day, and catching up with the other chasers by phone that revealed that all scored severe storms. The Hunter crew had scored a damaging supercell. I was pleased that all crews suceeded. The images below show some turbulence in a weak microburst. The storm persisted for an hour or two after dark giving a lovely lightning show ( click to see full image ) A photo taken earlier in day shows a rain shaft being undercut by outflow of a storm further south ( right ) MAPS & STUFF The MSL reveals a significant trough over most of the state. Lift Index figures were also negative across much of the state. You would have scored a thunderstorm anywhere except for the far NE today. LI's are questionable considering supercell storms formed in the upper Hunter valley ( Approx 32.30S, 151E ). Helping the supercell situation were favorable upper level winds - see the 200hpa winds chart, note that the scale is in metres a second, (* 1.942 to get knots ). This was the first day of the chase in which upper winds were at least moderate.
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