Valid: Mon 27 Feb 2017 06:00 to Tue 28 Feb 2017 06:00 UTC
Issued: Sun 26 Feb 2017 23:53
Forecaster: VAN DER VELDE
A level 1 was issued for W France mainly for isolated tornadoes and severe convective wind gusts.
The arrival of a large scale Atlantic trough to the European continent will destabilize an area from Bristish Isles, Benelux countries to central France, up to southern Scandinavia and Germany, with expected ML/MUCAPE values under 150 J/kg. A slight diurnal effect can be seen in the GFS model. A shortwave trough and associated 300 hPa left exit region of a strong westerly jet is predicted to move from W France to Netherlands and Denmark between 06Z and 00Z. This region has the most solid CAPE signals and is crossed by the left fringe of the jet, resulting in strong deep layer shear (25 m/s). Low level shear is also enhanced to 10-13 m/s at 0-1 km, although helicity is maximized east of the region with CAPE. An isolated tornado is possible, and severe convective wind gusts can occasionally reach 25 m/s.