Flash Flood Warning 87, NWS Nashville, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
350 AM CST TUE NOV 30 2004

.DISCUSSION...
BAND OF NUMEROUS SHOWERS SET UP ACROSS MIDDLE TENNESSEE OVERNIGHT,
WITH KOHX INDICATING MODERATE TO HEAVY RAINS OVER A GOOD PART OF
OUR FORECAST AREA (ESPECIALLY FROM WAYNESBORO...TO FRANKLIN...
AND GALLATIN).

EXPECT A LOW PRESSURE SYSTEM TO MOVE NORTHEAST FROM THE LOWER
MISSISSIPPI VALLEY THIS AFTERNOON AND STRENGTHEN. LOW LEVEL JET
INCREASES ACROSS MUCH OF MIDDLE TENNESSEE AND GFS INDICATES 50 KT
WINDS WORKING ALL THE WAY DOWN TO NEAR 900 MB THIS AFTERNOON. TOTAL
TOTALS WILL BE IN THE UPPER 40S ACROSS OUR SOUTHERN COUNTIES AND
CANT RULE OUT THE POSSIBILITY THAT A FEW THUNDERSTORMS COULD
TAP STRONG LOW LEVEL WIND FIELD AND BRING SOME STRONG WINDS TO THE
SURFACE. STRENGTHENING LOW LEVEL WIND ENVIRONMENT COUPLED WITH
MARGINALLY HIGH TOTAL TOTALS SUGGESTS THE POSSIBILITY FOR SOME HEAVY
RAIN PRODUCING CONVECTION AS WELL AS THE POTENTIAL FOR ISOLATED
SEVERE STORMS OVER ABOUT THE EASTERN TWO THIRDS OF OUR FORECAST AREA.

HAVE ONCE AGAIN GONE WITH A GFS/NGM BLEND, KEEPING MAIN RAIN BAND
PARKED OVER THE SAME GENERAL AREA THROUGH 18Z, THEN PROGRESSING
EASTWARD DURING THE AFTERNOON AND EVENING.

SINCE FLASH FLOOD POTENTIAL WITH THIS SYSTEM APPEARS MARGINAL, HAVE
DECIDED TO ONLY ISSUE WATCH FOR THE AREA THAT IS MOST VULNERABLE TO
AN EXTENDED PERIOD OF MODERATE TO HEAVY RAINFALL (WHICH IS GENERALLY
EAST OF A SPRINGFIELD TO WAYNESBORO LINE).

PASSAGE OF STRONG LOW PRESSURE SYSTEM TONIGHT WILL BRING SOME GUSTY
WEST TO NORTHWEST WINDS INTO THE MID STATE, ALONG WITH COOLER
TEMPERATURES. COOL SURFACE RIDGE MOVES OVER WEDNESDAY NIGHT AND
ALLOWS FOR FREEZING TEMPERATURES AREA-WIDE.

EXPECT NEXT CHANCE FOR RAIN TO COME LATE IN THE WEEK. SO, AFTER THE
DELUGE TODAY, WE SHOULD BE ABLE TO SQUEEZE OUT A FEW DAYS OF DRY
WEATHER.
&&

.BNA WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH EAST OF A SPRINGFIELD TO WAYNESBORO LINE

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HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
523 AM CST TUE NOV 30 2004

TNZ005>011-022>034-056>066-075-077>080-093>095-011030-
BEDFORD-BENTON-CANNON-CHEATHAM-CLAY-COFFEE-CUMBERLAND-DAVIDSON-
DEKALB-DICKSON-FENTRESS-GILES-GRUNDY-HICKMAN-HOUSTON-HUMPHREYS-
JACKSON-LAWRENCE-LEWIS-MACON-MARSHALL-MAURY-MONTGOMERY-OVERTON-PERRY-
PICKETT-PUTNAM-ROBERTSON-RUTHERFORD-SMITH-STEWART-SUMNER-TROUSDALE-
VAN BUREN-WARREN-WAYNE-WHITE-WILLIAMSON-WILSON-
523 AM CST TUE NOV 30 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...TODAY

A LOW PRESSURE SYSTEM WILL MOVE ACROSS THE TENNESSEE VALLEY
TODAY AND EARLY TONIGHT AND PRODUCE WIDESPREAD RAIN...ALONG WITH
THE POSSIBILITY OF LOCALIZED FLOODING OVER PARTS OF MIDDLE TENNESSEE.
A FLOOD WATCH IS IN EFFECT THROUGH EARLY TONIGHT FOR AREAS EAST OF A
SPRINGFIELD TO WAYNESBORO LINE. RAIN TOTALS BETWEEN ONE AND HALF AND
TWO INCHES WILL BE COMMON IN THE WATCH AREA...WITH SOME HIGHER
AMOUNTS POSSIBLE.

RAINFALL WILL LIKELY PRODUCE PONDING OF WATER ON ROADS AND IN
SOME POORLY DRAINED AREAS. SOME RIVERS AND STREAMS MAY ALSO RISE TO
NEAR BANKFULL.

ISOLATED THUNDERSTORMS ARE ALSO POSSIBLE THROUGH EARLY TONIGHT...
AND A FEW COULD PRODUCE STRONG...GUSTY WINDS...ESPECIALLY IN
AREAS NEAR THE ALABAMA BORDER.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED.

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