Storm Forecast
Valid: Sat 30 Jan 2010 06:00 to Sun 31 Jan 2010 06:00 UTC
Issued: Sat 30 Jan 2010 05:31
Forecaster: VAN DER VELDE

A level 1 was issued for SW Turkey mainly for a chance of an isolated tornado / hail

A level 1 was issued for S Italy, W Albania and W Greece for isolated excessive convective rain.

SYNOPSIS

One of the more convective setups this winter. A longwave upper trough has installed over Europe, and cold air spreads from the north into Western Europe behind a cold front associated to a low pressure center over northern Germany/Poland. Mid level lapse rates are steep in the cold air, and wintry showers are likely, also deeper inland in eastern UK, Belgium, Netherlands, northern France, Germany, Denmark and southern Norway. A polar low-like trough will sink southward into the North Sea and is currently predicted to make landfall in Belgium or SW Netherlands at 18Z by GFS18Z. A strong polar low is predicted by the same model as well as ECMWF to round SW Norway by the end of this forecast period.
A low over Italy sends a cold airmass over the Mediterranean resulting into numerous thunderstorms which should be most dense in coastal convergence zones and near mid level vorticity maxima. An upper shortwave trough moves south of Turkey to the east under the jetstream.

DISCUSSION

...SW Turkey, Cyprus...

Presence of CAPE overspread by strong DLS (jet) and SREH values by backed low level flow could lead to supercells with chance of large hail and tornadoes. However, the QG forcing will turn to downward motion in late morning, suppressing any storms. The predicted convergence zone lies in the sea rather than at the south coast of Turkey.

... S Italy, W Albania and W Greece...

Persistent landfall of convective cells may locally lead to flash floods as result of excessive rain sums.