Severe Thunderstorm Warning 187, NWS Paducah, KY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
1256 PM CDT THU JUN 26 2008

.DISCUSSION...
ANY CONVECTIVE ACTIVITY IN THE NEAR TERM WILL BE ISOLD OR WIDELY
SCT IN NATURE AND DIURNALLY BASED...SO MAINTAINING 20 POPS OR SO
TO ACCOUNT FOR THEIR POSSIBILITY...ALTHOUGH CURRENT RADAR PICS
SHOW MOST DEVELOPMENT IS TO OUR EAST AND WEST. IF THIS DRIER
APPROACH HOLDS TRUE THAT WOULD GIVE MORE WEIGHT TO THE DRIER
GFS...BUT BOTH GFS/NAM SAG A FRONTAL BOUNDARY SOUTH LATE FRIDAY
NIGHT...WHICH YIELDS A SLGT RISK THAT COMES A KNOCKING ON OUR NRN
DOORSTEP. THE SLIGHT RISK THEN TRANSLATES SOUTH ACROSS FA W/FROPA
SAT AND SIMILARLY WE WILL GRADUALLY INCREASE POPS TO/NEAR THEIR
PEAK WITH/ALONG THE FRONT FROM LATE FRI NIGHT-SAT-EARLY SAT NIGHT.
2NDARY UPPER TROF PASSAGE MIGHT LINGER AN OVERNIGHT SAT NIGHT POP
AS WELL. THE TRENDING OF THE 12Z GFS/NAM IS SLIGHTLY SLOWER THAN
PREVIOUS RUNS SO THAT SHOULD BE PAID ATTENTION TO NEXT RUN IN CASE
IT ENDS UP BEING SAT-SUN VERSUS LATE FRI NIGHT-SAT...BUT FOR NOW
WE GO W/FROPA AND BRING BACK DRY WEATHER BY SUN.

THAT ESTABLISHES DRIER/SLIGHTLY COOLER PATTERN FOR MEDIUM TO LONG
RANGE DAYS 4-8 (SUN-THU). THE GFS YIELDS STRONG NLYS-NWLYS THAT
DRAG DRIER/COOLER AIR ACROSS QUAD STATE THRU TUE/INTO WED...WHICH
SHOULD PRODUCE NR/SLIGHTLY BELOW CLIMATOLOGICAL NORMS FOR LATE JUNE
HIGHS/LOWS. THEN SOME AIR MASS MODIFYING LATER IN THE MID-LATE
WEEK WILL SPELL A SLIGHT REBOUND IN TEMPS/HUMIDITIES...CLOSER TO
SEASONAL NORMS. THU-FRI MIGHT SEE RETURN TO A DIURNAL POP BUT
WERE LAYING OFF FOR NOW.

THE MODELS MOS VARIES FROM THE COOLER/WETTER MET TO THE
DRIER/HOTTER MAV. THE FWC OFFERS A COMPROMISING LEAN TOWARD THE
MAV AND MIGHT BE OUR PREFERRED ROUTE...OR CLOSE TO IT...FOR THE
SHORT RANGE. FIND WE TWEEKED SLIGHTLY COOLER THAN HPC TOWARD GFS
BASED MEX MOS INTO THE LONG RANGE GIVEN ITS RUN-RUN SUCCESSIONS
SUGGESTING THE SAME.

&&

.AVIATION...
THIS DISCUSSION WILL BE MORE CONDITIONAL...ESPECIALLY FOR THE TIME
PERIOD FROM 18Z THROUGH 24Z TODAY /THURSDAY/...AS ANY SIGNIFICANT
COVERAGE OF CUMULUS OR SCATTERED SHOWER/THUNDERSTORM ACTIVITY HAS
YET TO DEVELOP OVER THE TAF SITES WITHIN THE WFO PAH FORECAST AREA.

HOWEVER...FOR THE KPAH AND KCGI TAF SITES...I ANTICIPATE SCATTERED
CUMULUS DEVELOPMENT NO LATER THAN 19Z...MAINLY IN THE 3-4KFT AGL
LEVEL. FROM 19Z THROUGH 23Z...I FURTHER ANTICIPATE SOME ISOLATED TO
SCATTERED SHOWER AND THUNDERSTORM DEVELOPMENT. SINCE THIS
DEVELOPMENT IS SOMEWHAT CONDITIONAL ON THE POSITION OF A MID/UPPER
LEVEL TROUGH PASSAGE AND INTERSECTION WITH LOW LEVEL INSTABILITY...I
HAVE CURRENTLY LIMITED THE KCGI/KPAH TAF SITES TO VICINITY
THUNDERSTORM MENTION AND A BROKEN 5-6KFT AGL CLOUD DECK WITH
BUILDING CB MENTION. MOST OF THIS ACTIVITY SHOULD BE DIURNAL AND
THIN OUT BY 01Z FRIDAY. AFTER THAT TIME...INTRODUCE SCATTERED CLOUD
DECKS BETWEEN ROUGHLY 2.5-4.5KFT AGL...WITH A BROKEN MID DECK
BETWEEN 7-10KFT DURING THE OVERNIGHT HOURS. BY FRIDAY MORNING...I BRING
BACK A SCATTERED 4KFT AGL DECK...WITH MINOR GUSTS ASSOCIATED WITH
THE TURNING OVER OF THE NOCTURNAL INVERSION.

A SIMILAR PATTERN IS EXPECTED WITH THE KEVV/KOWB TAF SITES...BUT
WITHOUT ANY MENTION OF NEARBY CONVECTIVE ACTIVITY. THE CHANCE FOR
SHOWERS AND THUNDERSTORMS MAY HAVE TO BE MONITORED IN AND NEAR THE
KOWB TAF SITE TODAY...AT LEAST THROUGH 23Z FRIDAY.

&&

.PAH WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
MO...NONE.
IL...NONE.
IN...NONE.
&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PADUCAH KY
242 PM CDT THU JUN 26 2008

ILZ075>078-080>094-INZ081-082-085>088-KYZ001>022-MOZ076-086-087-
100-107>112-114-271000-
JEFFERSON-WAYNE IL-EDWARDS-WABASH-PERRY IL-FRANKLIN-HAMILTON-
WHITE-JACKSON-WILLIAMSON-SALINE-GALLATIN-UNION IL-JOHNSON-POPE-
HARDIN-ALEXANDER-PULASKI-MASSAC-GIBSON-PIKE-POSEY-VANDERBURGH-
WARRICK-SPENCER-FULTON-HICKMAN-CARLISLE-BALLARD-MCCRACKEN-GRAVES-
LIVINGSTON-MARSHALL-CALLOWAY-CRITTENDEN-LYON-TRIGG-CALDWELL-
UNION KY-WEBSTER-HOPKINS-CHRISTIAN-HENDERSON-DAVIESS-MCLEAN-
MUHLENBERG-TODD-PERRY MO-BOLLINGER-CAPE GIRARDEAU-WAYNE MO-CARTER-
RIPLEY-BUTLER-STODDARD-SCOTT-MISSISSIPPI-NEW MADRID-
242 PM CDT THU JUN 26 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHERN
ILLINOIS...SOUTHWEST INDIANA...WESTERN KENTUCKY...AND SOUTHEAST
MISSOURI.

.DAY ONE...THIS AFTERNOON AND TONIGHT

ISOLATED THUNDERSTORMS ARE POSSIBLE. NO WIDESPREAD SEVERE WEATHER
IS ANTICIPATED AT THIS TIME. THE MAIN THREAT WILL BE LOCALLY HEAVY
RAIN AND LIGHTNING.

FLOODING WILL CONTINUE ON THE MISSISSIPPI AND BIG MUDDY RIVERS...
INCLUDING MODERATE FLOODING ON PARTS OF THE MISSISSIPPI RIVER.
REFER TO THE LATEST WARNINGS AND STATEMENTS FOR MORE DETAILED
INFORMATION.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THERE IS A CHANCE OF THUNDERSTORMS FRIDAY THROUGH SATURDAY NIGHT.
A COLD FRONT WILL MOVE ACROSS THE REGION ON SATURDAY AND OFFER
THE BEST CHANCES FOR STORMS...INCLUDING STRONG STORMS...SATURDAY
AFTERNOON OR EVENING. THERE IS A SLIGHT RISK OF SEVERE STORMS
SATURDAY...WITH THE MAIN THREATS LIKELY DAMAGING WINDS OR LARGE
HAIL...IN ADDITION TO A HEAVY RAIN AND LIGHTNING THREAT.

FLOODING WILL CONTINUE ON SOME AREA RIVERS. REFER TO THE LATEST
WARNINGS AND STATEMENTS FOR MORE DETAILED INFORMATION.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS SHOULD MAINTAIN ALERT STATUS IN CASE THEIR ACTIVATION IS
REQUESTED SOMETIME SATURDAY.