Storm Forecast
Valid: Tue 06 Feb 2007 06:00 to Wed 07 Feb 2007 06:00 UTC
Issued: Tue 06 Feb 2007 01:28
Forecaster: VAN DER VELDE

SYNOPSIS

A large mid-level trough is present over most of Europe. One low surface pressure areas within it moves from the Baltic Sea into Russia, while another one remains near western Denmark. A convective arctic mesoscale front sinks slowly southward over the North Sea and will reach the northern Netherlands around 00Z Wednesday (10m convergence GFS). Some lines of convection are forecast to be active over the southern North Sea, with a sporadic/isolated thunder around the low, mainly later in the period, likely bringing some snow and graupel. There is practically no vertical shear.

A shortwave trough with a small theta-e plume moves through the western Mediterranean Sea and is likely to cause some thunderstorms here and there, most precipitation forecast along western Corsica/Sardegna and western Italy. In this area there is also no shear of importance, so no severe weather is expected.

North of the Iberian Peninsula a disturbance will pass during 21Z-06Z, a shortwave trough with a low-level moisture plume unstable enough for some thundery activity... GFS indicates fairly high low-level shear (>12 m/s) and helicity values (>250 m2/s2), also enhanced deep layer shear (>20 m/s), mostly over Galicia. However, the model does not let instability exist as the moisture axis comes ashore, as a nocturnal inversion may have settled by that time, so there appears no need for a level 1 for sporadic tornadic activity chances.