Severe Thunderstorm Warning 265, NWS Nashville, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
300 PM CDT FRI SEP 20 2002

MAIN BATCH OF SHOWERS AND STORMS MOVING FROM WEST INTO MID TN THIS
AFTERNOON. COLD FRONT ALREADY IN FAR WEST TN. MODELS VARY SOMEWHAT
WITH PROGRESS OF FRONT THROUGH THE MID STATE TONIGHT. WITH SUPPORT
FROM LATEST RUC AND MESOETA...WILL LEAN TOWARD FASTER AVN.
REGARDLESS OF TIMING...MODELS SUGGEST BAND OF RAIN WILL BECOME
THINNER AND WEAKEN A BIT AS IT MOVES ACROSS THE MID STATE. STILL
SOME THREAT FOR SEVERE...BUT WITH LOSS OF HEATING THIS EVENING...DO
NOT BELIEVE THREAT IS WIDESPREAD. LOCALLY HEAVY RAINFALL WILL
OCCUR.

RAIN SHOULD END FOR OUR FAR WESTERN ZONES SUCH AS DOVER AND CAMDEN
BY 800 PM OR SO. MOST RAIN WILL END FOR NASHVILLE AND VICINITY
BEFORE MIDNIGHT. PLATEAU ZONES STILL EXPECTED TO HAVE BRUNT OF RAIN
FROM LATE EVENING INTO EARLY MORNING HOURS.

BASED ON AVN MODEL...NO POPS WILL BE CARRIED FOR MOST OF MID TN
SATURDAY. PLATEAU GROUP WILL HAVE A CHANCE. WILL LEAN WITH MORE
AGGRESSIVE AVN AND BRING DECREASING CLOUDS OVER MID TN. MODEL
DIFFERENCES CONTINUE INTO SUNDAY. NGM WANTS TO BRING MOISTURE BACK
INTO MID TN AND GENERATES QPF AS ANOTHER SHORTWAVE AND FRONT
APPROACHES. WILL GO WITH DRIER AVN MODEL BASED ON IDEA THAT DEEP
MOISTURE WILL STAY TO OUR SOUTHEAST AND WEAK FRONT WILL BRING JUST A
PERIOD OF CLOUDINESS.

REST OF FORECAST WILL REMAIN DRY WITH RELATIVELY COOLER AND LESS
HUMID PATTERN. FUTURE OF TROPICAL MOISTURE STILL IN QUESTION FOR
EXTENDED PERIOD.

CCF TEMPERATURE NUMBERS WILL BE CLOSE TO MOS.

.BNA...NONE.
SH

TNZ005>011-022>034-056>066-075>080-093>097-211030-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
1130 AM CDT FRI SEP 20 2002

AT MIDDAY...A COLD FRONT WAS LOCATED ALONG THE MISSISSIPPI RIVER AND
WILL CONTINUE TO MOVE EASTWARD CROSSING MIDDLE TENNESSEE LATE THIS
EVENING THROUGH SATURDAY MORNING.  AS THIS COLD FRONT MOVES
EASTWARD...MOISTURE...AVAILABLE POTENTIAL ENERGY AND WIND SHEAR WILL
CONTINUE TO ALLOW FAVORABLE CONDITIONS FOR THUNDERSTORM ACTIVITY
LATE THIS AFTERNOON AND EVENING. THERE IS A THREAT THAT SOME
THUNDERSTORMS MAY BECOME SEVERE...PRODUCING DAMAGING WIND AND HAIL.
ATMOSPHERIC CONDITIONS COULD ALLOW FOR THE DEVELOPMENT OF ISOLATED
SUPERCELL THUNDERSTORMS. THUS...ISOLATED TORNADOES CANNOT BE RULED
OUT.

IN ADDITION TO THE THREAT OF SEVERE WEATHER...ABUNDANT ATMOSPHERIC
MOISTURE WILL CAUSE LOCALLY HEAVY RAINFALL ACROSS MIDDLE TENNESSEE.

ACTIVATION OF EMERGENCY MANAGERS AND SPOTTERS MAY BECOME NECESSARY
FOR THIS AFTERNOON AND EVENING. STAY TUNED TO YOUR LOCAL NOAA
WEATHER RADIO...NEWS MEDIA...RADIO AND INTERNET SOURCES FOR THE
LATEST WEATHER INFORMATION ON THIS DEVELOPING WEATHER SITUATION.

SH/MED