CONVECTIVE FORECAST
VALID 06Z WED 09/04 - 06Z THU 10/04 2003
ISSUED: 08/04 22:22Z
FORECASTER: GROENEMEIJER

GENERAL THUNDERSTORMS ARE FORECAST ACROSS THE CENTRAL MEDITERRANEAN REGION AND SOUTHEASTERN SPAIN

SYNOPSIS

THERE IS A HIGH-OVER-LOW BLOCK IN PLACE WITH A HIGH OVER WESTERN NORWAY AND A RETROGRADING LOW OVER NORTHERN GERMANY. THERE IS A MODERATE WESTERLY MID/UPPER FLOW OVER THE MEDITERRANEAN. A VORT MAX OVER SOUTHERN FRANCE IS EXPECTED TO MERGE WITH A SOUTHWEST-NORTHEAST ORIENTED TROUGH OVER SOUTHERN IBERIA AND MOROCCO AND MOVE EASTWARD. OVER MUCH OF EUROPE A COLD STABLE AIR-MASS IS IN PLACE THAT CANNOT SUSTAIN WIDESPREAD THUNDERSTORMS. EXCEPTION IS EASTERN SPAIN AND CENTRAL MEDITERRANEAN.

DISCUSSION

...ITALY AND SURROUNDING AREA...
OVER THE WESTERN AND CENTRAL MEDITERRANEAN A NORTHWARD FLOW OF SLIGHTLY UNSTABLY WARM AIR WILL BECOME ESTABLISHED. A STATIONARY FRONTAL BOUNDARY OVER ITALY AND THE THYRRENEAN SEA WILL MOVE NORTHWARD AS A WARM FRONT. SOME THUNDERSTORMS ARE EXPECTED TO FORM BOTH NEAR THE WARM FRONT AND WITHIN THE WARM AIR MASS. MODERATE SHEAR PROFILES WILL SUSTAIN MOSTLY MULTICELL DEVELOPMENT. GIVEN LOW INSTABILITY, OVERALL RISK OF SEVER WEATHER IS LOW. HOWEVER, GIVEN 30-35 KT 850HPA WINDS OVER THE SOUTH OF THE FORECAST AREA SOME STRONG GUSTS MAY OCCUR, POSSIBLY APPROACHING THE SEVERE LIMIT OF 50KT IN PLACES.

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