As mentioned in an earlier email The Toolara State Forest near 26.0S 152.9E
(between Gympie AWS and Double Island Point AWS) suffered major damage on
Australia Day when 400 hectares of Pine Plantation (trees 18 -20 years old)
were destroyed. The sfc to 700hPa shear this day was probably the weakest
of the whole week of severe storms  but the CAPE may have been
extraordinarily large. The damage occurred around 0600UTC so plugging in
the Double Island Point 0500UTC T/TD of 32/25 into the Brisso 23Z trace
gives CAPE of 6286J/Kg while using Gympie's readings of  35/25 gives 6973
J/Kg.

Harald Richter

With 25 C dewpoints and massive CAPE you would have had massive wet (high
water loading) updraughts.  With a significant sub-cloud layer (as indicated
by moderate T-Td) I see microburst potential and cold pool dynamics ...

Harald

Jeff Callaghan

Hi Harold what I did not mention that there was an AWS at Toolara (not at
the damage site) which at 0500UTC had T/TD of 37/22. The 22 did not agree
with any of the other surrounding obs which all had 24 to 25 dewpoints  .
If this obs was correct, from your reasoning the hot drier air over the
damage should I presume make the microburst much worse. However this makes
the game much harder trying to identify such pockets of air.
Jeff