Forecast Update
Valid: Tue 24 Jun 2008 16:00 to Wed 25 Jun 2008 06:00 UTC
Issued: Tue 24 Jun 2008 16:41
Forecaster: SCHLENCZEK

SYNOPSIS

Please refer to the convective forecast.

DISCUSSION

... Austria, eastern Switzerland, northern Italy...

Convective initiation took place over western France and VIS satellite images show TCU over the Vosges mountains. A strong, possibly right-moving cell over southwestern Austria / northeastern Italy is expected to persist for some hours in a moderately sheared environment with about 1 kJ/kg MLCAPE. As convective cells stay more discrete, they probably become supercells, capable of producing widespread large / isolated very large hail and a few damaging gusts. Convection will become more elevated after sunset and a severe MCS may form in the late evening.

The region over W-central France has been downgraded because of less instability than anticipated by GFS with only moderate deep layer shear.

...S Belgium, Luxembourg, western Germany...

Southern parts of Belgium, Luxembourg and western Germany have been included in the level-one area as recent GFS runs suggest convective initiation in that region during the evening / night hours. A MCS is expected to form, capable of producing severe gusts and isolated large hail.

...Ireland, northern UK...

Recent soundings show very little instability and cloud top temperatures near or above -10°C which means that electified convection is rather unlikely. The thunderstorm area has been removed for that reason.
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