Forecast Update
Valid: Fri 14 Dec 2007 16:00 to Sat 15 Dec 2007 06:00 UTC
Issued: Fri 14 Dec 2007 16:35
Forecaster: TUSCHY

SYNOPSIS

Please refer to the outlook issued at Thu 13 Dec 2007 20:24 .

DISCUSSION

...Central Mediterranean...

There are no significant changes in what we expect but we decided to highlight a broad area of the central / western Mediterranean. Thunderstorms already occured over parts of the Adriatic Sea and the Tyrrhenian Sea and thermodynamic stratification only gets more favorable for thunderstorms to develop.
As upper-level low enters the Adriatic Sea during the evening hours, offshore flow should somewhat relax and hence the airmass has more time to mix over the warm sea waters, which should also increase the chance for thunderstorms over the central Adriatic Sea. In addition, thunderstorms should go on over the western Adriatic Sea and the Ionian Sea.
Latest sounding reports indicate very steep LL lapse rates, covering the Adriatic Sea and in combination with dewpoints just above 0°C ( e.g. east coast of Italy, where onshore flow is present with dewpoints of 0-2°C ) significant instability release mainly at lower levels will be present and we again want to emphasize the chance for an isolated waterspout report.

We also highlighted parts of the western Mediterranean, as thunderstorms now look more likely.