DAY 2 CONVECTIVE OUTLOOK
VALID 00Z SAT 04/01 - 06Z SUN 05/01 2003
ISSUED: 03/01 00:44Z
FORECASTER: HAVEN

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS BAY OF BISCAY, SW-FRANCE

GENERAL THUNDERSTORMS ARE FORECAST ACROSS PARTS OF ITALY, ADRIATIC SEA, CNTRL MEDITERRANEAN SEA

SYNOPSIS

BROAD ZONAL JETSTREAM WITH SEVERAL EMBEDDED SHORTWAVES REMAINS OVER THE MEDITERRANEAN SEA AND S-CENTRAL EUROPE. LARGE UPPER TROUGH EXPECTED OVER WRN MEDITERRANEAN SEA SATURDAY EVENING. FRONTAL WAVE SATURDAY AT 00Z OVER ADRIATIC SEA MOVES OVER SE-EUROPE IN THE MORNING. MAIN BAROCLINIC ZONE FROM POLAND TO BENELUX TO NW-FRANCE SURGES SOUTHEAST AS A COLDFRONT WHICH IS EXPECTED FROM CSECH REPUBLIC TO CNTRL ALPES TO LIGURIAN SEA IN THE EVENING. DEVELOPING SFC CYCLONE IVOF AUSTRIA BY THEN.

DISCUSSION

...BAY OF BISCAY, SW-FRANCE...
CONVECTIVE MIXING WILL BE DEEP ENOUGH FOR SOME TSTMS ALONG AND S OF COLDFRONT. HIGH /50+ KT WINDSPEEDS AT 850 HPA/ WILL BE TRANSPORTED TO THE SURFACE BY DOWNDRAFTS IN SHOWERS/TSTMS, WHICH CAN RESULT IN SEVERE WINDGUSTS. ACTIVITY IS EXPECTED TO DECREASE DURING THE NIGHT.

...ADRIATIC SEA...
MARGINAL LAPSE RATES /NEARLY MOIST ADIABATIC/ WILL SUPPORT SOME THUNDER POTENTIAL WHEN COMBINED WITH PREFRONTAL LOW LEVEL WARMING AND FRONTAL LIFT IN THE BEGINNING OF THE FORECAST PERIOD. SECOND PEAK IN THUNDER POTENTIAL IS EXPECTED SATURDAY EVENING AND SUNDAY NIGHT AS TROUGH ALOFT APPROACHES...AND ASSOCIATED LARGE SCALE MIDLEVEL DESTABILIZATION STEEPENS LOW-MIDLEVEL LAPSE RATES. SOME ISOLATED NON-SEVERE WINDGUSTS MAY OCCUR WITH THIS ACTIVITY. ELSEWHERE IN THE CNTRL MEDITERRANEAN...ISOLATED LIGHTNING STRIKES ARE POSSIBLE.

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