At upland locations or where lee-wave motion
plays a part, and where instability breaks across the zone of strongest
gradient (dry air intrusion aloft ... as pointed out by David), then
such gusts could occur ... indeed, given *vigorous* instability,
free-air at even higher levels can be brought down to the surface in
isolated spots. This is why warnings etc., are so difficult to write in
these situations - v

Camborne and (and Watnall) soundings at 12Z show the dry air intrusion down to very low levels-
http://weather.uwyo.edu/cgi-bin/soun...400&STNM=03808
The Aberystwyth profiler shows the jet,disturbances in the tropopause and slantwise and vertical
(convective) circulations at lower levels (i think-have no expertise at interpreting these)
http://mst.nerc.ac.uk/plots_mst_latest.html

Anybody know the highest gust reported in the Sw y'day?


--
regards,
david
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