Tornado Warning 6, NWS Paducah, KY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
241 AM CDT SUN SEP 2 2001

MAIN FORECAST CONCERN WILL BE PRECIP CHANCES/LOCATION WITH THE
APPROACH OF AN UPPER LEVEL S/W TROUGH APPROACHING TENNESSEE.

AT 05Z...A S/W TROUGH PASSING THROUGH EASTERN TEXAS WAS HELPING TO
FIRE THUNDERSTORMS NEAR THE PALESTINE PROFILER. MODEL GUIDANCE IS IN
FAIRLY UNIFORM AGREEMENT OF PROGRESSING THIS S/W TROUGH NORTHEAST
THROUGH ARKANSAS AND INTO WESTERN TENNESSEE TODAY. THIS SOUTHERN
BRANCH WAVE IS PROGGED TO GET HUNG UP TONIGHT SOMEWHERE OVER THE
TENNESSEE VALLEY AS ANOTHER S/W TROUGH...CURRENTLY OVER NORTHWEST
KANSAS...IS PROGGED TO DIP SOUTH INTO THE LOWER MISSISSIPPI
VALLEY...AND ALONG WITH THIS FIRST TEXAS SYSTEM...HELP CARVE OUT A
MORE PRONOUNCED TROUGH OVER THE GULF COAST STATES NORTH INTO THE
TENNESSEE VALLEY.

WITH A STATIONARY FRONT NEAR THE MO/AR AND TN/KY BORDERS...AND
PLENTY OF JUICE AVAILABLE JUST SOUTH OF THE FRONT...AS EVIDENT BY
02/00Z RAOB DERIVED PRECIPITABLE WATERS OF 1.99 AND 1.62 AT KLZK AND
KOHX RESPECTIVELY...PRECIPITATION FIRING ALONG AND PRIMARILY SOUTH
OF THE FRONT LOOKS PROMISING TODAY AND TONIGHT. CURRENT ZONE POPS
SUPPORT THIS PATTERN. ALSO...CURRENT ZONE FORECAST SKY CONDITION
WORDING ALSO MATCHES THIS PATTERN. TEMPERATURE TODAY AND TONIGHT
ALSO LOOK ON TRACK.

A SIGNIFICANT CANADIAN LOW WILL PROGRESS INTO THE EASTERN
PROVIDENCES BY MID-WEEK AND HELP DROP A COLD FRONT INTO THE FORECAST
AREA TUESDAY. THIS FEATURE WILL ALSO HELP EJECT THE TENNESSEE VALLEY
LOW EAST OF THE REGION. HOWEVER...BEFORE THIS HAPPENS...ENOUGH
RESIDUAL MOISTURE ON THE NORTHWEST SIDE OF THE TENNESSEE LOW MAY
HELP PROMPT SOME LINGERING SHOWERS IN MY SOUTHEAST COUNTIES FOR
LABOR DAY. CURRENT FORECAST ALSO REFLECTS THIS.

WITH THE BULK OF THE LOW LEVEL MOISTURE PUSHED SOUTH AND EAST OF THE
AREA...THE NEXT QUESTION WILL BE WHETHER THE AREA RECEIVES PRECIP
WITH TUESDAY/S FROPA. THE 02/00Z RUN OF THE AVN INDICATES A QPF OF
ONE TO TWO TENTHS ACROSS THE AREA ASSOCIATED WITH THE FROPA. THE
02/00Z RUN OF THE CANADIAN MODEL SHOWS A DRY FROPA. CURRENT FORECAST
INDICATES A PARTLY CLOUDY SKY. THIS IS A GOOD COMPROMISE OF THE TWO.
LATER SHIFTS WILL NEED TO MONITOR HOW THIS SITUATION DEVELOPS.

WILL MAKE NO CHANGES TO THE REMAINDER OF THE EXTENDED FORECAST GIVEN
LIMITED NEW DATA PAST TUESDAY ATTM. CONCERNED THOUGH THAT MID TO
LONG RANGE MODELS MAY DO SEVERAL TIMING CHANGES OF UPSTREAM SYSTEMS
OVER THE NEXT FEW RUNS GIVEN THE CURRENT DOWNWARD TREND IN THE
ATMOSPHERIC ANGULAR MOMENTUM AND ALSO GIVEN THE CURRENT MOIST PHASE
OF THE MJO IS REACHING ITS PROJECTED MID-POINT. THE ECMWF MODEL MAY
BE THE ONE TO WATCH OVER THE NEXT WEEK AS IT TENDS TO HANDLE THESE
GLOBAL CHANGES THE BEST.

.PAH...NONE.

SLEIGHTER