Flash Flood Warning 55, NWS Paducah, KY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
115 PM CDT WED MAY 28 1997

...THE FORECAST CHALLENGE FOR TONIGHT WILL BE...HOW LONG THE SHOWER AND
THUNDERSTORM ACTIVITY WILL LAST AND ITS EFFECT ON TEMPERATURES ACROSS
THE AREA...

17Z SURFACE CHART SHOWS THAT THE LOW PRESSURE SYSTEM HAS MOVED INTO
SIL NEAR MVN. THE WARM FRONT EXTENDED FROM THERE TO JUST SOUTH OF
EVV. THE TRAILING COLD FRONT EXTENDED SOUTH FROM THE LOW TO JUST EAST
OF UNO MO. MOVEMENT OF THE LOW PRESSURE SYSTEM IS CONSISTENT WITH THE
ETA MODEL MOVEMENT WHICH WAS FOLLOWED. THE LOW IS EXPECTED TO BE OVER
NORTHERN IL BY 12Z THURSDAY...SO THE TRAILING COLD FRONT WILL BE SLOW
TO MOVE EAST OF THE FA ONLY REACHING WKY BY 12Z THURSDAY.

AS A RESULT...SHOWERS AND THUNDERSTORMS CAN BE EXPECTED FOR MOST OF THE
NIGHT ACROSS THE FA WITH THE BEST CHANCE EAST OF THE MISSISSIPPI RIVER.
SOME OF THE STORMS MAY BECOME SEVERE THIS EVENING AS THE FA IS IN A
SLIGHT RISK FOR SEVERE WEATHER. WITH THE TROPICAL AIRMASS AND DRY AIR
IN THE MID LEVELS EXPECTED TO MOVE EAST INTO THE AREA TONIGHT WITH THE
APPROACH OF THE COLD FRONT...ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE.
DUE TO THE PROXIMITY OF THE LOW AN ISOLATED TORNADO CANNOT BE RULED
OUT. LIMITING FACTORS ARE THE LACK OF SUNSHINE AND THE WEAK WIND
FIELDS. SATELLITE SHOTS SHOW MOST OF THE FA WITH CLOUDY SKIES WITH SOME
BREAKS OVER WESTERN KENTUCKY. IF CLEARING BECOMES WIDESPREAD ACROSS THE
FA...SEVERE THUNDERSTOR@MS WILL BECOME MORE PROBABLE.

WITH CLOUDY SKIES EXPECTED OVERNIGHT...WARMER FWC NUMBERS WERE PREFERED
OVER ALL THE AREA EXPECT SOUTHEAST MISSOURI WHERE WITH FRONTAL PASSAGE
...COOLER FAN NUMBERS WERE FAVORED THERE.

ML/GL

THUNDERSTORM OUTLOOK - VALID UNTIL 7OO AM THURSDAY MONRING
NATIONAL WEATHER SERVICE PADUCAH KY
1100 AM CDT WED MAY 28 1997

...SLIGHT RISK OF SEVERE THUNDERSTORMS OVER ALL OF THE FOUR STATE
REGION THIS AFTERNOON AND EVENING...

A PERSISTENT LOW PRESSURE SYSTEM CONTINUES OVER THE MID MISSISSIPPI
VALLEY WITH AN ASSOCIATED WARM FRONT CURRENTLY EXTENDING FROM THE
CONFLUENCE OF THE MISSISSIPPI AND OHIO RIVERS TO NEAR HOPKINSVILLE.
THE WARM FRONT IS EXPECTED TO MOVE NORTH OF THE FOUR STATE REGION THIS
AFTERNOON BRINGING WARM MOIST AIR. THIS WITH THE APPROACH OF A SLOW
MOVING COLD FRONT OVER SOUTHEAST MISSOURI WILL RESULT IN SHOWERS AND
THUNDERSTORMS.

HIGH MOISTURE CONTENT OF THE AIR WHEN CONBINED WITH WARMER TEMPERATURES
WILL MAKE THE AIR INCREASINGLY UNSTABLE THIS AFTERNOON. ALSO DRY AIR
IN THE MID LEVELS OF THE ATMOSPHERE MOVING OVER THE MOIST AIR IN THE
LOWER LEVELS WILL FURTHER DESTABILIZE THE AIR..HENCE THE SLIGHT RISK FOR
SEVERE THUNDERSTORMS. WINDS...HOWEVER...BOTH NEAR THE SURFACE AND ALOFT
ARE EXPECTED TO REMAIN WEAK WHICH WILL SERVE AS ONE LIMITING FACTOR ON
SEVERE STORM DEVELOPMENT. A MORE IMPORTANT LIMITING FACTOR WILL DEPEND
ON WHETHER OR NOT THE SKY CLEARS. MORE SUN WILL MEAN FURTHER
DESTABILIZATION.

THE MAIN THREAT WITH THESE STORMS WILL BE DAMAGING STRAIGHT LINE WINDS
AND LARGE HAIL. DUE THE PROXIMITY OF THE LOW PRESSURE SYSTEM...AN
ISOLATED TORNADO CANNOT BE RULED OUT. STORM MOVEMENT WILL BE NORTHEAST
AT 20 MPH.

SPOTTER ACTIVATION MAY BE NECESSARY LATER THIS AFTERNOON AND EVENING.

ML/GL

THUNDERSTORM OUTLOOK - VALID UNTIL 7OO AM THURSDAY MONRING
NATIONAL WEATHER SERVICE PADUCAH KY
1100 AM CDT WED MAY 28 1997

...SLIGHT RISK OF SEVERE THUNDERSTORMS OVER ALL OF THE FOUR STATE
REGION THIS AFTERNOON AND EVENING...

A PERSISTENT LOW PRESSURE SYSTEM CONTINUES OVER THE MID MISSISSIPPI
VALLEY WITH AN ASSOCIATED WARM FRONT CURRENTLY EXTENDING FROM THE
CONFLUENCE OF THE MISSISSIPPI AND OHIO RIVERS TO NEAR HOPKINSVILLE.
THE WARM FRONT IS EXPECTED TO MOVE NORTH OF THE FOUR STATE REGION THIS
AFTERNOON BRINGING WARM MOIST AIR. THIS WITH THE APPROACH OF A SLOW
MOVING COLD FRONT OVER SOUTHEAST MISSOURI WILL RESULT IN SHOWERS AND
THUNDERSTORMS.

HIGH MOISTURE CONTENT OF THE AIR WHEN CONBINED WITH WARMER TEMPERATURES
WILL MAKE THE AIR INCREASINGLY UNSTABLE THIS AFTERNOON. ALSO DRY AIR
IN THE MID LEVELS OF THE ATMOSPHERE MOVING OVER THE MOIST AIR IN THE
LOWER LEVELS WILL FURTHER DESTABILIZE THE AIR..HENCE THE SLIGHT RISK FOR
SEVERE THUNDERSTORMS. WINDS...HOWEVER...BOTH NEAR THE SURFACE AND ALOFT
ARE EXPECTED TO REMAIN WEAK WHICH WILL SERVE AS ONE LIMITING FACTOR ON
SEVERE STORM DEVELOPMENT. A MORE IMPORTANT LIMITING FACTOR WILL DEPEND
ON WHETHER OR NOT THE SKY CLEARS. MORE SUN WILL MEAN FURTHER
DESTABILIZATION.

THE MAIN THREAT WITH THESE STORMS WILL BE DAMAGING STRAIGHT LINE WINDS
AND LARGE HAIL. DUE THE PROXIMITY OF THE LOW PRESSURE SYSTEM...AN
ISOLATED TORNADO CANNOT BE RULED OUT. STORM MOVEMENT WILL BE NORTHEAST
AT 20\ MPH.

SPOTTER ACTIVATION MAY BE NECESSARY LATER THIS AFTERNOON AND EVENING.

ML/GL