CONVECTIVE FORECAST
VALID Thu 16 Jun 06:00 - Fri 17 Jun 06:00 2005 (UTC)
ISSUED: 15 Jun 17:29 (UTC)
FORECASTER: Christoph Gatzen

SYNOPSIS

Between well-developed long-wave trough NW of British Isles and a upper high that ridges into Bay of Biscay, a rather strong jet is directed towards British Isles. Broad upper delta flow pattern dominates most of Europe ... with extended upper ridge over northeastern Europe and cut-off lows over northern Mediterranean and southeastern Europe ... and upper level winds/ QG forcing are expected to be quite weak during the period over most of the forecast region. At lower levels ... warm and unstable airmass is present form central Mediterranean to eastern Europe. Warm maritime airmass advects into Great Britain.

DISCUSSION

...TSTMS region ...
To the east of a frontal boundary reaching from western Poland to southern Alpine region ... warm airmass is present ... characterized by steep to neutral mid-level lapse rates and quite rich low-level moisture over central Mediterranean and along the frontal boundary over eastern Europe. Thunderstorms are expected to form in this airmass as on Wednesday. Severe thunderstorms seem to be quite unlikely as vertical wind shear will be low over most of the affected region. Due to interaction of outflow boundaries ... an isolated mesocyclone is not ruled out ... capable of producing large hail and severe wind gusts. Best chances for mesocyclones should exist over Black Sea region, where deep layer wind shear will be strongest. Another region with enhanced deep layer wind shear will be central Mediterranean and Greece, where instability is expected to be significantly lower. Allover threat seems to be low. Local flash-flooding due to slow moving thunderstorms seem to be the most important threat.

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