Severe Thunderstorm Warning 73, NWS Jackson, KY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON KY
245 AM EDT THU MAY 15 2003

THE MAIN CONCERN WITH THIS MORNING/S FORECAST DEALS WITH PCPN
CHANCES THROUGH THE PERIOD. ATTM...SCATTERED SHRA/TSRA WAS FOUND
ACROSS E KY IN AN AREA OF UPPER DIVERGENCE AHEAD OF UPPER LOW
SPINNING ACROSS IA.  MODELS ARE IN FAIR AGREEMENT THAT THIS UPPER
LOW ROTATES THROUGH SOUTHERN GREAT LAKES TODAY...WITH AN UPPER LEVEL
SHORT WAVE PUSHING THROUGH OUR FORECAST AREA LATE THIS AFTERNOON AND
EARLY THIS EVENING. GFS IS FASTER MOVING THIS SYSTEM THROUGH...BUT
THE TREND HAS BEEN TO SLOW IT DOWN...THUS WILL USE THE ETA FOR
TIMING OF THE SYSTEM TODAY. THIS WOULD SUGGEST BEST CHANCE FOR
STRONGEST T-STORMS TO OCCUR BETWEEN 18Z-00Z. BUFKIT FCST SOUNDINGS
SHOW A FAIRLY LOW WBZ...SO WOULD THINK HAIL WOULD BE THE PRIMARY
SEVERE WEATHER THREAT TODAY. WITH A DEEP MOISTURE PROFILE
FCST...WILL CONTINUE LIKELY POPS ACROSS THE FORECAST AREA. WITH
CLOUDS IN PLACE TODAY...WILL GO A COUPLE OF DEGREES COOLER THAN
GUIDANCE VALUES WHICH KEEPS HIGHS IN THE LOWER 70S FOR MOST
LOCATIONS.

UPPER WAVE SHIFTS EAST OF THE FORECAST AREA BY 06Z TONIGHT...SO HAVE
DECREASED POPS IN OUR WESTERN MOST ZONES...BUT KEPT A GOOD CHANCE IN
FAR EASTERN ZONES EARLY. OTHERWISE...ONLY CHANGE WAS TO BUMP UP LOWS
IN NORTHERN LOCATIONS.

WHILE MODELS STILL DIFFER ON THE EVOLUTION OF STRONG UPPER WAVE
PUSHING INTO WRN AZ ATTM...IT APPEARS MOST OF E KY WILL BE BETWEEN
SYSTEMS ON FRIDAY...WITH A WEAK MEAN RIDGE LOCATED OVER OUR AREA.
HOWEVER...BOTH THE GFS AND ETA SUGGEST A WEAK UPPER LEVEL SHORT WAVE
TRAVERSES THROUGH THIS RIDGE ACROSS TN LATE FRIDAY. TO BETTER MATCH
SURROUNDING OFFICE/S GRIDS...WILL INTRODUCE A SLIGHT CHANCE OF PCPN
TO OUR SOUTHERN ZONES FRIDAY AND FRIDAY NIGHT. WITH A GOOD INCREASE
IN 1000-850MB THICKNESS FORECAST...WILL INCREASE HIGHS ON FRIDAY A
COUPLE OF DEGREES.

THERE STILL REMAINS MUCH UNCERTAINTY ON THE TRACK AND TIMING OF OUR
WEEKEND WEATHER SYSTEM...ALTHOUGH THE LATEST GFS RUN IS SLOWER AND
FURTHER SOUTH THAN IT/S PREVIOUS RUN...WHICH IS STARTING TO COME
MORE IN LINE WITH THE ETA SOLUTION. HOWEVER...THE LATEST ETA RUN
POSITIONS THIS SYSTEM A LITTLE FARTHER NORTH AND EAST THAN IT/S
PREVIOUS RUN. THUS...EXPECT THE REAL OUTCOME TO BE SOMEWHERE BETWEEN
LATEST GFS/ETA GUIDANCE. THEREFORE...WILL UNDERCUT AVN MOS GUIDANCE
FOR POPS SAT...WHICH PREVIOUS FCST HAS WELL HANDLED....AND KEEP CHC
POPS FOR SAT AND SUNDAY.

.JKL...NONE.

HYSELL

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PREVIOUS DISCUSSIONS FOLLOW:
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845 PM EDT WED MAY 14 2003

AT 00Z GRIDDED FORECAST TEMPERATURES LOOK RIGHT ON TARGET WITH
OBS...GENERALLY WITHIN A DEGREE. CURRENT DEWPOINTS AROUND 50 BUT
WITH CLOUDS CURRENT FORECAST LOWS IN THE MID 50S LOOK ON TRACK.
UPPER LOW IN THE UPPER MS VALLEY WITH SHORT WAVE TROF ROTATING
AROUND BRINGING THUNDERSTORMS TO NORTHERN ILLINOIS AND INDIANA.
BASED ON TRENDS AND 18Z MESOETA COULD SEE REMAINS OF THIS CONVECTION
COME INTO OUR CWA BEFORE DAYBREAK THURSDAY. JKL RADAR SHOWING
SCATTERED LIGHT SHOWERS OVER THE WESTERN PART OF THE CWA BUT THEY
ARE DECREASING. CHC POPS STILL LOOK GOOD TONIGHT...WITH BEST CHANCE
LATE AS DEPICTED IN GRIDDED FORECAST DATA. GRIDDED POPS IN GOOD
AGREEMENT WITH NEIGHBORING WFOS AND DO NOT PLAN ANY FORECAST
CHANGES AT THIS TIME.

SBH

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400 PM EDT WED MAY 14 2003

BIG CONCERN IS POPS AND SEVERE POTENTIAL FOR THURSDAY.

WARM FRONT IS CURRENTLY IN THE PROCESS OF LIFTING NORTH ACROSS THE
CWA. WEAK SHORTWAVE WILL HELP KICK OFF SHOWERS AND SOME
THUNDERSTORMS TONIGHT.

SEVERE THREAT TOMORROW FOR ESPECIALLY HAIL.  WET BULB ZERO HEIGHTS
WILL BE RELATIVELY LOW WITH STEEP LAPSE RATES AND AMPLE MOISTURE.
DAMAGING WIND WILL ALSO BE A THREAT...ALTHOUGH MID-LEVEL WIND NOT
PARTICULARLY STRONG.  COLD AIR ADVECTION AT MID-LEVELS ALSO HELPING
THE SEVERE THREAT. CULPRIT FOR STIRRING UP PROBLEMS WILL BE A
SHORTWAVE DIVING DOWN FROM THE NORTHWEST.  LOOKS LIKE IT COULD START
CAUSING SEVERE THREAT AS EARLY AS AROUND 15Z.  MODELS LOOK AS IF
THEY ARE A LITTLE WEAK WITH THIS SYSTEM ON THURSDAY...THEREFORE I AM
COMFORTABLE WITH MENTIONING WIND AND HAIL IN FORECAST AND GOING WITH
LIKELY POPS. WENT WITH 60 POPS INSTEAD OF MY ORIGINAL 80 POPS FOR
TOMORROW TO MATCH BETTER WITH SURROUNDING OFFICES

THE UPPER LEVEL PATTERN WILL REMAIN TOWARD THE STATIC SIDE AS
BLOCKING HIGH OVER EASTERN CANADA AND TROUGH OVER NORTHWESTERN CONUS
PERSISTS.

TENDED TO SIDE WITH MORE CONSERVATIVE TEMPS IN THE NEAR TERM GIVEN
CLOUD COVER.  WENT FAIRLY CLOSE TO REASONABLE NGM AND MAV MOS POPS.

EXTENDED...UPPER LEVEL LOW TRACKING ACROSS THE SOUTHERN U.S. WILL
WORK SLOWLY INTO THE REGION BY SATURDAY AFTERNOON. THE LOW CUTS OFF
AND HANGS UP OVER THE SOUTHEAST U.S. THROUGH EARLY MONDAY. THE LOW
THEN TRACKS OFF TO THE NORTHEAST IN RESPONSE TO A SECOND WAVE AND
ASSOCIATED COLD FRONT...WHICH MOVES INTO THE REGION BY WEDNESDAY.
GENERALLY...FROM THAT POINT ON...WE APPEAR TO BE MOVING INTO A MORE
PROGRESSIVE PATTERN. HOWEVER...BEING THAT FAR OUT...ITS WAIT AND SEE.

WILL HAVE TO KEEP AN EYE ON THE SYSTEM FOR THIS WEEKEND AS THE SPEED
AND TRACK OF THE STORM WILL MORE THAN LIKELY MEAN PLENTY OF
RAINFALL. WITH ALL OF THE RAINFALL OF THE PAST COUPLE OF
WEEKS...FLOODING MIGHT BECOME A PROBLEM...ESPECIALLY WITH ANY
THUNDERSTORMS. HPC HAS AREA UNDER 2 TO 3 INCH POTENTIAL FOR
RAINFALL. BEST CHANCE FOR THUNDERSTORMS APPEARS TO BE ON SUNDAY WITH
DECENT LIFT. HOWEVER...FOR NOW INSTABILITY DOESNT LOOK REAL
IMPRESSIVE.

HEINLEIN/RAY
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940 AM EDT WED MAY 14 2003

FCST CONCERN THIS MORNING IS CLOUD COVER AND EFFECT ON TEMPS.
APPEARS CLOUD COVER MOVED IN ABOUT 9Z THIS MORNING. SAT PICS SHOW
SOME CLEARING TAKING PLACE AND THE SUN IS PEAKING OUT.
HOWEVER...PICS ALSO SHOW SOME REDEVELOPMENT OF AC IN CNTRL KY. SO
WHILE THERE WILL BE SOME CLEARING...THE OVERALL TREND IS TO INCREASE
CLOUDS...WHICH CURRENT FCST ADDRESSES. LATEST MOS APPEARS TO BE
RUNNING A FEW DEGREES HIGH ON TEMPS. WITH CLOUDS ON THE INCREASE
AGAIN THIS AFTERNOON...WILL KEEP HIGHS WHERE THEY ARE AT...WITH
HIGHS OF 70 TO 75...A COUPLE OF DEGREES BELOW GUIDANCE.

WARM FRONTAL BOUNDARY CONTINUES TO SET UP ACROSS AREA IN RESPONSE TO
LOW PRESSURE MOVING INTO MIDWEST. THIS BOUNDARY MOVES VERY SLOWLY
NORTHEAST SETTING UP OPPORTUNITY FOR PRECIP THIS AFTERNOON AND
TONIGHT. CURRENT FCST ADDRESSES THIS AS WELL. OVERALL...NO CHANGES
TO CURRENT FCST.

RAY
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KYZ044-050>052-058>060-068-069-079-080-083>088-104-106>120-161200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE JACKSON KY
430 AM EDT THU MAY 15 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN KENTUCKY.

.DAY ONE...TODAY AND TONIGHT.

THE STORM PREDICTION CENTER HAS PLACED ALL OF SOUTHEAST KENTUCKY
UNDER A SLIGHT RISK FOR SEVERE WEATHER TODAY. ADDITIONAL
THUNDERSTORMS ARE FORECAST TO ERUPT ACROSS SOUTHEAST KENTUCKY
EARLY THIS AFTERNOON. THE PRIMARY THREAT FROM THESE STORMS IS LARGE
HAIL...ALTHOUGH STRONG WINDS ARE ALSO POSSIBLE. WHILE SEVERE WEATHER
IS POSSIBLE ACROSS ALL OF SOUTHEAST KENTUCKY...THE GREATEST CHANCES
FOR SEVERE WEATHER WILL BE WEST OF A MOUNT STERLING TO PINEVILLE
LINE.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

SHOWERS AND A FEW THUNDERSTORMS ARE POSSIBLE IN EXTREME SOUTHERN
KENTUCKY FRIDAY AND FRIDAY NIGHT. A STRONGER STORM SYSTEM WILL BRING
A BETTER CHANCE FOR THUNDERSTORMS TO ALL OF SOUTHEAST KENTUCKY
SATURDAY AND SUNDAY...WHILE MORE THUNDERSTORMS ARE IN THE FORECAST
FOR WEDNESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED THIS AFTERNOON AND EARLY THIS
EVENING.

HYSELL

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE JACKSON KY
1041 AM EDT THU MAY 15 2003

TIME(EDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1006 AM    HINDMAN                   KY   0.75 IN HAIL
05/15/03   KNOTT                          ALONG HIGHWAY 80

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