Hi David,......... as the surface low moved north colder air in
depth pushed east and the PV forcing associated with the trough released the
potential instability with dramatic consequences.........
Will.
Cheers Will,
Herstmonceux 00Z shows instabilty but vertical development limited by slightly drier and warmer air
aloft

http://weather.uwyo.edu/cgi-bin/soun...500&STNM=03882

--
regards,
david
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