Forecast Update
Valid: Sat 20 May 2006 11:00 to Sun 21 May 2006 06:00 UTC
Issued: Sat 20 May 2006 11:40
Forecaster: GROENEMEIJER/DAHL

SYNOPSIS

Refer to Storm Forecast...

DISCUSSION

Benelux, Germany, France...

A strong 45 m/s mid-level jet moves eastward over France. Destabilisation is taking place in its left-exit region, where a dry intrusion punches into the cloudiness of an occluded frontal system.

The destabilisation has lead to widespread convective storms, that are producing severe gusts in excess of 25 m/s and small hail in places. Storms show signatures of bows and occasionally marginal supercell characteristics. The activity will likely shift further eastnortheastward in the coming hours.

SSEly winds over west-central Germany suggest that enhanced helicity may become available to the storms and risk of supercells will increase with an attendant tornado threat.
An upgrade to level 2 will be considered... and may be issued within a couple of hours.