Storm Forecast
Valid: Tue 02 May 2006 06:00 to Wed 03 May 2006 06:00 UTC
Issued: Tue 02 May 2006 01:23
Forecaster: VAN DER VELDE

SYNOPSIS

Large scale southern flow over much of Europe between an Atlantic low near Ireland and a large high pressure area over Russia advects increasingly warmer air northward. In the mid-upper levels there is still a broad upper trough present. Two old fronts are stalling over central Europe with the flow parallel to their orientation, and undergo frontolysis.

DISCUSSION

...Central Europe, western Balkan...

With insolation expected to increase, destabilization should be sufficient to support the GFS model CAPE of a few hundred J/kg by late afternoon, and isolated storms will likely form over a large area, mainly orographic features. Shear is insignificant.

...Iberian Peninsula, France...

A thermal low has formed over the Iberian Peninsula and northern Africa and will give some thunderous activity again today.
Destabilization also takes place over SW France, but an upper ridge will prevent deep convection.

...northern Algeria...

Very steep midlevel lapse rates and BL moisture at the north side of the mountains create several hundred J/kg CAPE. More importantly, with moderate to fairly strong deep layer shear and more than 300 m2/s2 storm-relative helicity, storms can grow to supercells and produce mainly large hail and severe gusts. However, the concern is that much of the instability is capped. Expect isolated severe storms at most.