Severe Thunderstorm Warning 147, NWS Paducah, KY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
1250 PM CDT SUN SEP 23 2001

PRIMARY CONCERNS IN THE SHORT TERM ARE POPS/SEVERE WEATHER CHANCES
THIS AFTERNOON AND EVENING...WITH FOCUS TURNING TO WRAPAROUND
MOISTURE AND HOW LONG IT WILL LINGER ACROSS THE AREA.

UPPER-LEVEL TROUGH MOVING EAST OUT OF IOWA INTO NORTHWEST ILLINOIS
AT MIDDAY WILL PUSH A PREFRONTAL TROUGH ACROSS THE AREA LATE THIS
AFTERNOON AND THIS EVENING WITH THE TRUE COLD FRONT ARRIVING LATER
TONIGHT.  AHEAD OF THE PREFRONTAL TROUGH...NO CU FIELD NOTED ON
SATELLITE...INDICATIVE OF THE LACK OF SIGNIFICANT LOW-LEVEL MOISTURE
ACROSS THE AREA...WHILE TEMPERATURES WARMED INTO THE LOW TO MID
80S.  THE AVN INDICATES A LITTLE MORE INSTABILITY THAN THE MESOETA
TODAY...WITH VALUES AS LOW AS -6 ACROSS THE AREA BY LATE AFTERNOON.
THE PREFRONTAL TROUGH APPEARS TO BE RATHER DIFFUSE OVER SOUTHEAST
MISSOURI AT THIS TIME...AS IT HAS NOT FOCUSED SIGNIFICANT CU DEVELOPMENT.
BOTTOM-LINE IS THAT WITH DECENT INSTABILITY AND CONSIDERABLE MID AND
UPPER-LEVEL DYNAMICS AND STRENGTHENING WIND FIELDS AT ALL
LEVELS...SEVERE WEATHER IS A STRONG POSSIBILITY ACROSS PORTIONS OF
THE FORECAST AREA.  THE AREAL COVERAGE IS IN DOUBT THOUGH AS MOS
POPS CAN ONLY BARELY EEK OUT LIKELY LEVELS THIS EVENING IN THE
EAST...AS THE SURFACE SYSTEM TAKES BETTER SHAPE.  WILL CONTINUE WITH
LIKELY POPS WITH A SEVERE MENTION FOR THIS EVENING IN MOST
LOCATIONS...BUT MAIN ACTION MAY BE INTO CENTRAL PORTIONS OF THE
FORECAST AREA BY 00Z.  WILL MAKE FINAL DECISION ON FIRST PERIOD POPS
SHORTLY BEFORE ISSUANCE.

NORTHWEST WINDS SHOULD PICK UP LATER TONIGHT FROM WEST TO EAST AS
CANADIAN HIGH PRESSURE BEGINS TO BUILD INTO THE AREA.  THE AVN AND
MESOETA TO A LESSER EXTENT HOLD ON TO HIGH 850MB MOISTURE THROUGH
THE NIGHT IN MOST ZONES AND THROUGH MONDAY NIGHT IN THE NORTHEAST.
WILL RE-INTRODUCE A SLIGHT CHANCE OF WRAPAROUND SHOWERS WITHIN THIS
MOISTURE TOMORROW AFTERNOON...AS SUPPORTED BY ALL AVAILABLE GUIDANCE
FOR EVV.  HOWEVER...WOULDNT BE TOO SURPRISED IF IT ONLY AMOUNTS TO
SPRINKLES.

THE ENTIRE AREA SHOULD SEE MOSTLY CLEAR SKIES FROM TUESDAY THROUGH
AT LEAST THE FIRST HALF OF NEXT WEEKEND...WITH COOL BUT MODERATING
TEMPERATURES THROUGH THE END OF THE WEEK.  LOWS MAY FLIRT WITH THE
UPPER 30S IN THE NORTHERN ZONES...BUT THE FWC MOS FOR 00Z KEEPS
SURFACE DEWPOINTS IN THE LOW TO MID 40S...SO WILL KEEP LOWS AT OR
ABOVE 40 IN ALL ZONES FOR NOW.

THE MRF AND ECMWF BOTH SHOW A CLOSED UPPER-LOW DESCENDING TOWARD THE
AREA WITH THE MRF BEING QUICKER...BRINGING IT INTO THE AREA BY
SUNDAY.  THIS SYSTEM WILL HAVE LITTLE OR NO SURFACE REFLECTION AND
MOISTURE WILL BE NON-EXISTENT.  THEREFORE WILL INDICATE A FEW MORE
CLOUDS FOR SUNDAY...BUT WILL KEEP IT DRY.

WILL SIDE WITH THE MAV TEMPERATURE GUIDANCE THROUGH TONIGHT AND
MONDAY...AND THEN WITH THE WARMER FWC FOR MONDAY NIGHT AND TUESDAY.

.PAH...NONE.

DRS

ILZ075>078-080>094-INZ081-082-085>088-KYZ001>022-MOZ076-086-087-100-
107>112-114-231830-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE PADUCAH KY
1130 AM CDT SUN SEP 23 2001

THIS THUNDERSTORM OUTLOOK IS FOR SOUTHEAST MISSOURI...SOUTHERN
ILLINOIS...SOUTHWEST INDIANA...AND WESTERN KENTUCKY. IT IS VALID
UNTIL 600 AM MONDAY.

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND
EVENING OVER THE QUAD STATE REGION.

A STRONG COLD FRONT WILL SWEEP SOUTHEAST THROUGH SOUTHERN ILLINOIS
AND SOUTHEAST MISSOURI AROUND MID AFTERNOON...THEN THROUGH SOUTHWEST
INDIANA AND WESTERN KENTUCKY LATER THIS AFTERNOON AND EARLY TONIGHT.
A STRONG AREA OF LOW PRESSURE ALOFT WILL ACCOMPANY THE FRONT. IN
ADDITION...SOLAR HEATING WILL DESTABILIZE THE AIR ACROSS THE REGION.

FORECAST WIND PATTERNS ALOFT SUGGEST THE MAIN STORM THREAT WILL BE
DAMAGING WIND GUSTS. HOWEVER...SCATTERED STORMS MAY ALSO PRODUCE HAIL
THE SIZE OF DIMES OR GREATER.

SPOTTER ACTIVATION MAY BE NECESSARY THIS AFTERNOON AND EARLY TONIGHT.

THE SEVERE STORM THREAT WILL END WITH THE PASSAGE OF THE STRONG COLD
FRONT EARLY TONIGHT. SOME OF THE COOLEST AIR SINCE LAST SPRING WILL
SPREAD OVER THE REGION MONDAY AND TUESDAY.

GM/RSU