Hail in Illinois, May 18, 2001

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
245 PM CDT FRI MAY 18 2001

MAIN CONCERN THIS FORECAST PACKAGE IS THE CHANCE FOR SHOWERS AND
THUNDERSTORMS TONIGHT AND EARLY SATURDAY. LATEST SURFACE ANALYSIS
INDICATED A COLD FRONT STRETCHING FROM SOUTHERN INDIANA OVER TO
ABOUT ST. LOUIS...THEN INTO OKLAHOMA. A WEAK WAVE OF LOW PRESSURE
WAS POSITIONED ALONG THE FRONT IN SOUTHWEST MISSOURI.

ALL MODELS HAVE COME INTO GOOD GENERAL AGREEMENT ON THE TIMING OF
BOTH SURFACE AND UPPER-LEVEL FEATURES. AS THE FRONT ENTERS THE
REGION TONIGHT...UPPER DYNAMICS...DEEP MOISTURE...AND INSTABILITY
ARE ALL IN PLACE FOR THE OCCURRENCE OF SHOWERS AND THUNDERSTORMS.
THIS EVENING...A 40 KNOT JET MAX IS FORECAST TO SWING JUST SOUTH OF
THE AREA. UNIDIRECTIONAL SPEED SHEAR AND MODERATE INSTABILITY AHEAD
OF THE SYSTEM COULD ENHANCE THE DAMAGING WIND POTENTIAL FROM SOME
STORMS. HOWEVER...THE MAIN FEATURE WITH THIS SYSTEM WILL BE LOCALLY
HEAVY RAIN...ESPECIALLY AS THE SYSTEM TRACKS ACROSS THE REGION
OVERNIGHT. THE STORM SYSTEM WILL LINGER CLOUDS AND A CHANCE OF
SHOWERS IN EASTERN COUNTIES SATURDAY MORNING. THEREAFTER...DRIER AIR
WILL WORK IN AND AID IN GRADUAL CLEARING FROM WEST TO EAST.

THE NEXT SYSTEM PUSHES A CHANCE OF SHOWERS AND THUNDERSTORMS OVER
THE AREA FROM LATE SUNDAY THROUGH MONDAY. A CUT-OFF LOW IS STILL
FORECAST TO DEVELOP SOMEWHERE FROM THE GREAT LAKES INTO THE OHIO
VALLEY EARLY NEXT WEEK. AS THE REGION IS THRUST INTO NORTHWEST
FLOW...COOLER THAN NORMAL TEMPERATURES ARE ANTICIPATED FOR MUCH OF
NEXT WEEK. GUIDANCE NUMBERS FROM BOTH THE AVN AND NGM LOOK GOOD AND
WILL GENERALLY FOLLOW A BLEND THROUGH THE PERIOD.

.PAH...NONE.

PRESLEY

ILZ075>078-080>094-INZ081-082-085>088-KYZ001>022-MOZ076-086-087-100-
107>112-114-182045-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE PADUCAH KY
250 PM CDT FRI MAY 18 2001

THE FOLLOWING OUTLOOK IS FOR SOUTHEAST MISSOURI...SOUTHERN
ILLINOIS...WESTERN KENTUCKY AND SOUTHWEST INDIANA...VALID UNTIL
600 AM SATURDAY.

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE ENTIRE
REGION THIS AFTERNOON AND TONIGHT.

EARLY THIS AFTERNOON...A POTENT UPPER LEVEL STORM SYSTEM WAS MOVING
EAST ACROSS SOUTHWEST MISSOURI AND NORTHWEST ARKANSAS. THE AIRMASS
HAS BECOME UNSTABLE ACROSS SOUTHERN INTO SOUTHEAST MISSOURI AHEAD OF
THIS FEATURE. THUNDERSTORMS WERE DEVELOPING RAPIDLY OVER SOUTHERN
MISSOURI AND NORTHERN ARKANSAS. AS THIS ACTIVITY MOVES EAST INTO A
MORE UNSTABLE ATMOSPHERE IN SOUTHEAST MISSOURI...AN INCREASE IN
INTENSITY IS EXPECTED...WITH SOME OF THE STORMS POSSIBLY BECOMING
SEVERE. WIND SHEAR HAS ALSO INCREASED...WHICH MAY ENHANCE THE
POTENTIAL FOR SUSTAINED INTENSITY...WITH A FEW OF THE STORMS
PRODUCING STRONG WIND AND MARGINALLY SEVERE HAIL. THE ACTIVITY WILL
LIKELY CONTINUE EAST INTO SOUTHERN ILLINOIS...WESTERN KENTUCKY AND
SOUTHWEST INDIANA INTO THE EVENING HOURS.

STORM MOTION IS EXPECTED TO BE EAST TO NORTHEAST AT 35 MPH.

SPOTTER ACTIVATION IS LIKELY IN SOUTHEAST MISSOURI LATE THIS
AFTERNOON AND EARLY THIS EVENING. ACTIVATION MAY BE REQUESTED IN
SOUTHERN ILLINOIS...SOUTHWEST INDIANA AND WESTERN KENTUCKY AS THE
EVENING WEARS ON.