Forecast Update
Valid: Wed 24 Mar 2010 10:00 to Thu 25 Mar 2010 06:00 UTC
Issued: Wed 24 Mar 2010 10:08
Forecaster: PUCIK

A level 1 was issued for Southern to Central Spain mainly for large hail and severe wind gusts.

SYNOPSIS

Refer to the Storm Forecast

DISCUSSION

...Spain...

Dewpoints observed across this area look reasonably well predicted by GFS and it seems the model is trustworthy in the development of MLCAPEs locally exceeding 500 J/kg. Moreover, satellite imagery revelas a dry slot over the area with little middle and high cloud cover, so that diurnally driven heating might apply. Predicted wind shear values for 0-3 and 0-6 km are still reasonable for the development of organised convection, including the possiblity of supercells. Due to the trough development close to the surface, slightly enhaced SREH values are simulated ( around 100-150 J/kg in 0-3 km layer). Forcing seems to be rather weak, probably only in the form of local convergence and therefore, only isolated to scattered storms are predicted. Large hail or severe wind gusts might occur especially in case supercells manage to develop and a Level 1 is warranted.

...France...

GFS and ECMWF have finally agreed on the development of diurnally driven showers and thunderstorms during the afternoon hours and a lightning area is necessary. MLCAPE values are predicted to be in order of hundreds J/kg with local convergence zones being a foci for the storm development. Very low chance of severe weather precludes issuance of Level at the moment.