Harald Richter commented:
Storm connoisseurs:
NSW and QLD had a classic severe weather setup last Saturday (24 Nov 01). It was the best
setup I have seen in Australia this year. I am (almost) amazed that there weren't any
tornado reports.
The 0500 UTC surface chart shows a clear moisture boundary running from Sydney to Moree to
Charleville, with good surface dewpoints (15 C upwards) E of that boundary.
Generally the surface winds shifted from NW to NNE when crossing that boundary from the W,
i.e. I'd expect some low-level convergence.
SSY showed more than 200 hPa of 8+ g/kg of moisture at 0400 UTC (special sounding !!??)
with the winds turning from 25/010 at the surface to 65/270 at 500 --> that is a potent
hodograph and a ~70 knot shear vector! Mid-level lapse rates were close to dry adiabatic
accounting for an eyeballed 2000 J/kg of CAPE for the 50mb mean surface parcel.
The wind field had no weaknesses. The only caveat was some capping at low levels,
requiring deep lift to get parcels to
their LFC.
The 2300 UTC MOR sounding also showed deep moisture, great turning of a consistenty stout
flow and promising lapse rates.
2300 UTC BCV had a hellofa cap at 850, but had 150 hPa of 12 g/kg leading to an eyeballed
4000 J/kg of CAPE. Gasp!
In other words, BCV had LI = -7.
The cap obviously broke later with a line of supercells stretching from N of Newcastle all
the way Charleville and beyond. Why do I think supercells? The shear in the
soundings is sufficient, the CAPE is ample, good turning of the winds, enough
ll moisture and all cells had 55+ dBZ reflectivities. The cell N of Newcastle was a
classic left-mover, consistent with the 0400 UTC anticlockwise hodograph out of SSY.
VIS showed large cold anvils.
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