Storm Forecast
Valid: Thu 15 Feb 2007 06:00 to Fri 16 Feb 2007 06:00 UTC
Issued: Thu 15 Feb 2007 05:43
Forecaster: GATZEN

SYNOPSIS

Amplified trough over north-eastern Atlantic yields a deep southerly flow over western Europe, advecting warm air mass originating from northern Africa into France. A intense frontal boundary is expected to the west, affecting western Iberian Peninsula and British Isles. To the east, rising geopotential is expected over Scandinavia, where a high develops. To the south of this high, cut-off lows move eastward over Mediterranean.

DISCUSSION

Southern Italy, Greece

Cut-off low moves eastward over central Mediterranean. In the range of this cut-off low, models suggest that instability will be present. Latest observations show that deep instability is not indicated by latest soundings, but rich low-level moisture has developed over southern Italy region, and given neutral to steep mid-level lapse rates indicated by soundings further north-west underneath that cut-off, instability will likely develop during the period. Expect that showers and thunderstorms will develop underneath the propagating cut-off today spreading further south-east into southern Italy region in the evening, and western Greece during the night. Although DLS is quite weak, favorable veering profiles indicated by easterly surface winds and southerly winds aloft may lead to 100 J/kg low-level helicity, and a few storms may organize especially near Greece. One or two MCS are expected to form, capable of producing strong wind gusts and intense rain. Embedded mesocyclones will also pose a thread of tornadoes. However, given weak instability, shear, and forcing, it seems that most convection will be non-severe.

Western Europe

Along the frontal boundary, showers and thunderstorms will likely affect extremely western Europe. Expect that deep instability will remain further W, organized thunderstorms are not forecast ATTM.