VALID 00Z THU 31/10 - 00Z FRI 01/11 2002
ISSUED: 31/10 02:34Z
FORECASTER: HAVEN

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS WESTERN MEDITERRANEAN SEA

GENERAL THUNDERSTORMS ARE FORECAST ACROSS THE AREA SURROUNDING THE SLIGHT RISK AREA, SOUTHEASTERN FRANCE

SYNOPSIS

POSITIVELY TILTED UPPER TROUGH OVER S-FRANCE TO S-SPAIN IS SLOWLY MOVING EAST. SHALLOW LOW AND ASSOCIATED SFC TROUGH OVER WRN MEDITERRANEAN AND S-FRANCE IS SLOWLY MOVING SOUTHEAST.

DISCUSSION

...WESTERN MEDITERRANEAN SEA...
00Z SOUNDING OF NIMES SHOWS UNSTABLE PROFILE ABOVD BOUNDARY LAYER. SFC CONVERGENCE NEAR SFC TROUGH AND UVM DUE TO THE UPPER TROUGH HAS LEAD TO TSTM CLUSTER IN GULF OF LION/MONTPELLIER AREA AND ISOLATED TSTMS FURTHER NORTH. VERTICAL WINDSHEAR IS INSUFFICIENT FOR ANY SEVERE THREAT IN THE CURRENT TSTM AREA. AS UPPER TROUGH MOVES EAST...TSTMS WILL DEVELOP OVER WRN MEDITERRANEAN. S OF 40N STRONGER WINDSHEAR EXISTS AS IS SHOWN BY 00Z SOUNDING OF LESJ. WITH WEAKENING CAP DUE TO DYNAMIC UVM, THIS WILL LIKELY RESULT INTO THE DEVELOPMENT OF STRONG MULTICELLS, PROBABLY WITH (MARGINAL) LARGE HAIL SINCE SBCAPE WILL CLIMB UP TO 1500 J/KG.

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