Storm Forecast
Valid: Wed 06 Feb 2013 06:00 to Thu 07 Feb 2013 06:00 UTC
Issued: Wed 06 Feb 2013 03:35
Forecaster: TUSCHY

Two level 1 areas were issued, one over W-CNTRL Italy and the other one along the E-coast of the Adriatic Sea mainly for heavy rain and an isolated tornado event.

SYNOPSIS and DISCUSSION

A major upper trough is placed over Europe with attendant - 30°C isotherm spreading far south, reaching N-Algeria during the evening and overnight hours. Despite a dry and cold air mass affecting most parts of Europe, steep mid-level lapse rates and regionally better BL moisture assist in numerous areas with thunderstorm probabilities. Obviously, the Mediterranean and adjacent areas will see the most widespread activity.

Most of the activity occurs beneath the base of the upper trough and therefore in a weakly sheared environment. Strong wind gusts and marginal hail will be the main hazard.

However, better shear and moderate MLCAPE overlap exists from the offshore areas of N-Algeria to the Tyrrhenian Sea to the Adriatic Sea. A lot depends also on the final strength and placement of the LL vortex, which sits over N-Italy and remains ill-defined. To its south, stronger onshore flow may advect better moistue ashore over part of C-Italy (between 06-15Z), where some onshore CAPE and strong shear overlap. An isolated tornado event (mainly along the coast or just onshore) and heavy rain will be the main hazard. A similar risk exists along the E-coast of the Adriatic Sea with heavy rain or snow affecting the level 1 area. Again an isolated tornado event can't be ruled out due to increasing shear along the coasts. Despite those risks, isolated large hail may accompany any storm from N-Africa to the Adriatic Sea, but level 1 areas were only added, where a multiple risk of weather phenomena exists.