On Fri, 27 Aug 2004 15:34:29 +0100, "Martin Rowley"
wrote:

... yes, it certainly is marked. All I can come up with atm is that the
00Z Watnall ascent (can't see the 12Z yet) which was in the warm air at
that time, *would* produce deep moist instability to the surface
temperature/dew point regime just ahead of the surface cold front - i.e.
Air temp ~19, dew point ~16 or 17. The key would be the surface temp
getting high enough as the AS thinned behind the upper cold (as Jon
noted above), allowing surface-based convection to be initiated and
'focussed' ahead of a PVA-maxima swinging around the upper trough (which
seems broad on the low-res charts I have available - so it will almost
certainly contain minor lobes of +ve vorticity) to both help initiation
and force the resultant convective elements to run 'in the flow'. The
thing we have here that _perhaps_ is not always present is the lobe of
notably high surface dew points that has been advected ENE'wards (as
noted in another thread).

Staggers back confused by all the two and three letter acronyms, camly
opens another stella, and says

whats all this mean in laymans terms?