Forecast Update
Valid: Tue 11 Nov 2008 01:00 to Tue 11 Nov 2008 06:00 UTC
Issued: Tue 11 Nov 2008 01:00
Forecaster: VAN DER VELDE

UPDATE

A cold front over France is associated with a line echo wave pattern (squall line). The development of this line corresponds with some signals of most-unstable (or vertically integrated) parcel instability in GFS. Large 0-2 line-normal component of 12-20 m/s is in support of bow echoes.

Bowing segments pose a threat of isolated severe gusts (>25 m/s). Currently gusts with speeds just below this threshold have been observed.

It is not excluded that in the strong 0-3 km SREH and 0-1 km shear environment (300-400 m2/s2 and >15 m/s respectively) and low LCL heights, embedded cells in the line can obtain rotation and produce a tornado.

The probability of lightning however seems low.