Severe Thunderstorm Warning 57, NWS Paducah, KY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
120 AM CDT WED JUN 20 2001

KPAH 88D STILL ACTIVE WITH WIDELY SCATTERED CONVECTION FROM NEAR
PADUCAH TO JUST NORTH OF THE KY LAKES. ANOTHER AREA OF CONVECTION
WAS CONCENTRATED AROUND MOUNT VERNON IL. AIRMASS STILL RATHER
UNSTABLE...AND CONVECTION FORMING ALONG PREVIOUSLY CREATED
BOUNDARIES...AND IN AN 850MB THETA-E RIDGE ACROSS THE HEART OF THE
FA. THIS CONVECTION HAS PERSISTED SINCE WHAT FORMED EARLY YESTERDAY
AFTERNOON...AND DON'T SEE ANY REAL REASON FOR A CHANGE TO WHAT IS
GOING ON FOR THE REST OF THE EARLY MORNING.

HAVE PLACED MY FAITH IN THE AVN AND NGM...AS THEY HAVE BEEN MORE
CONSISTENT IN ADVERTISING CURRENT CONVECTION...AND FRONTAL
POSITIONING AND QPF TODAY THROUGH THURSDAY. ETA APPEARED TO BE TOO
FAST...AND MORE OPTIMISTIC ON CONVECTION NOT DEVELOPING...ESPECIALLY
YESTERDAY AFTERNOON.

FOR TODAY...WILL GO WITH SCATTERED SHOWER AND THUNDERSTORM WORDING
AS THE COLD FRONT...CURRENTLY FROM SW INDIANA INTO SE MISSOURI
SLIDES SOUTH AND EAST...TO A POSITION SOUTH OF THE CWFA LATER TODAY.
WILL ALSO CONTINUE WITH PESSIMISTIC CLOUD FORECAST...AND KEEP THE
WINDS VARIABLE IN DIRECTION...DUE TO CONVECTIVE INFLUENCE...AND THE
FRONT MOVING THROUGH.

TONIGHT LOOKS ABOUT THE SAME. WILL GO LIKELY POPS AS CONVECTION IS
FORECAST TO DEVELOP ACROSS THE FA BEHIND THE FRONT. THIS WILL BE IN
A REGION OF DEEPER MOISTURE...AND GOOD 1000-850MB FRONTOGENETICAL
FORCING AND BAROCLINICITY. LI'S PROGGED -1 TO -4...SO THUNDER STILL
APPEARS REASONABLE.

TRY TO AVOID A FLIP FLOP...BUT ALL 3 MODELS SUGGEST THAT MID TROP
FORCING AND BEST MOISTURE WILL NOT BE EAST AND SOUTH OF THE FA UNTIL
MIDDAY THURSDAY NORTH SECTIONS...AND LATE AFTERNOON SOUTH AT THE
EARLIEST. SO WILL HAVE TO ADD BACK THE CHANCE FOR CONVECTION TO
THE FORECAST FOR THURSDAY...ALL DAY SOUTH...AND UNTIL EARLY
AFTERNOON NORTH. AVN AND ETA ALSO DROP A VORT SOUTHEAST AS THE
TROF DIGS IN OVER THE EASTERN U.S. FRIDAY MORNING. AVN IS A BIT MORE
AGGRESSIVE WITH THIS FEATURE. A RIBBON OF MOISTURE IS FORECAST TO
DROP SOUTHEAST ACROSS MAINLY SOUTHERN ILLINOIS AND SOUTHWEST INDIANA
INTO NORTHWESTERN KENTUCKY UNTIL MIDDAY. WILL NOT GET CARRIED
AWAY...BUT WILL ADD MORE CLOUDS TO THE FORECAST FOR THURSDAY NIGHT
AND FRIDAY FOR THE CWFA. MAINLY PARTLY CLOUDY. NO CHANGES BEYOND
FRIDAY.

USED A BLEND OF GUIDANCE AND PREVIOUS ZFP NUMBE&RS.

.PAH...NONE.

NOLES

ILZ075>078-080>094-INZ081-082-085>088-KYZ001>022-MOZ076-086-087-100-
107>112-114-201900-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE PADUCAH KY
1145 AM CDT WED JUN 20 2001

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

A CHANCE OF THUNDERSTORMS EXISTS ACROSS THE ENTIRE AREA THIS
AFTERNOON THROUGH TONIGHT...HOWEVER NO SEVERE WEATHER IS EXPECTED.

A WEAKENING COLD FRONT WAS LOCATED FROM CENTRAL INDIANA THROUGH
SOUTHERN ILLINOIS AND INTO SOUTHEAST MISSOURI LATE THIS MORNING.
THE FRONT IS EXPECTED TO CONTINUE TO WEAKEN AS IT SAGS SOUTHWARD
THROUGH THE REMAINDER OF THE AREA THIS AFTERNOON INTO TONIGHT. A
BAND OF SHOWERS AND THUNDERSTORMS THAT HAS BEEN STRETCHED ACROSS
MUCH OF WESTERN KENTUCKY THROUGH THE MORNING HOURS...HAS PRODUCED
VERY HEAVY RAINFALL IN A VERY NARROW BAND.

ONGOING THUNDERSTORMS ARE EXPECTED TO WEAKEN EARLY THIS AFTERNOON.
HOWEVER...AN OUTFLOW BOUNDARY FROM THESE STORMS MAY SERVE AS A FOCUS
FOR FURTHER THUNDERSTORM DEVELOPMENT LATER THIS AFTERNOON.  IN
ADDITION...THUNDERSTORMS MAY DEVELOP ALONG THE FRONT...AS
TEMPERATURES WARM UP THIS AFTERNOON.  MODERATE INSTABILITY AND WEAK
WIND FIELDS WILL PREVENT THIS ACTIVITY FROM REACHING SEVERE LEVELS.
HOWEVER...ISOLATED HEAVY RAINFALL MAY RESULT IN SOME MINOR FLOODING
PROBLEMS...ESPECIALLY IN AREAS THAT HAVE RECENTLY RECEIVED HEAVY
RAINS. ANY STORMS THAT CONTINUE OR DEVELOP THROUGH THE AFTERNOON
SHOULD DISSIPATE WITH SUNSET.

MORE WIDESPREAD SHOWERS AND A FEW THUNDERSTORMS WILL BE POSSIBLE
BEHIND THE BOUNDARY OVERNIGHT...BUT THESE STORMS ARE ALSO EXPECTED
TO REMAIN WELL BELOW SEVERE LEVELS.

STORM MOTION BOTH THIS AFTERNOON AND TONIGHT IS EXPECTED TO BE
TOWARD THE NORTHEAST AT 10 TO 15 MPH.

SPOTTER ACTIVATION IS NOT ANTICIPATED.

DRS