SA, NT, NSW and Vic- Rain, storms and wind 2-5th of September

I think I thread should be started for this event. If my title is a bit broad, feel free to change it. It is just the system is quite large and will effect a large area.

First off, my main interest is thunderstorms which look increasingly likely across central and NE SA on Friday. Currently there is a nice tongue of very rich moisture in the NT extending into NE SA with due points of 17-20 C. A strong low-level jet should form in response to an approaching short-wave trough advecting this low-level moisture further south. With dew points in the high teens and temps around the mid-twenties, CAPE should be around 1000-1500 j/kg. With stronger heating, higher CAPE may be possible. Wind shear may be quite impressive, currently GFS has a 30 knot N'ly at 850 mbar along/ahead of the surface trough. Winds should be in the range of 50-60 knots at 500 mbar along/ahead of the trough. Lower-level winds should be NNE but may veer later in the day. This will, at least earlier in the day, result in reasonable turning in the lower-levels. If all goes well, the certainly should be sufficient shear and instability for supercells with large hail and damaging winds. The strong low-level shear may suggest the potential for tornadoes if the storm bases are low enough and a supercellular storm mode dominates over more linear convective modes. I don't want to hype that up though. I hope I haven't jinx it and I wish there was a radar further north in SA.

Michael

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