Severe Thunderstorm Warning 64, NWS Morristown, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
330 PM EDT THU MAY 12 2005

.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)...WEAK FRONTAL
BOUNDARY JUST TO OUR NORTH HAS BEEN THE MAIN AREA OF LOW LEVEL
CONVERGENCE THIS AFTERNOON.  PREVIOUS FORECAST AND GRIDS WERE SET UP
WELL TO HANDLE THIS WEAK BOUNDARY SAGGING SOUTH OVERNIGHT.  DECIDED
TO INCLUDE LOW POPS IN ALL AREAS TONIGHT...DUE IN PART TO THE AMOUNT
OF INSTABILITY (AS TEMPS HAVE CLIMBED WELL INTO THE 80 TO 90 DEGREE
RANGE) AND SOME ISOLATED STRONG STORMS THAT HAVE DEVELOPED OVER THE
SEQUATCHIE VALLEY COUNTIES...WHERE NO RAIN CHANCES WERE EARLIER
INCLUDED.  STORMS IN THIS AREA ARE UNDERNEATH THE UPPER LEVEL RIDGE
WHERE STEERING WINDS ARE EXTREMELY LIGHT...SO EXPECT JUST A SLOW
SOUTHWARD DRIFT OF THIS ACTIVITY OVER SE TN.

OTHERWISE...THE WEAK BOUNDARY LIFTS NE TOMORROW...WHICH LEAVES NO
CLEAR FOCUS FOR STORM DEVELOPMENT (OTHER THAN TERRAIN) UNTIL THE
UPPER LEVEL TROUGH AND COLD FRONT APPROACH BY LATE SATURDAY.  ONLY
SIGNIFICANT CHANGES WERE TO SLIGHTLY INCREASE RAIN CHANCES FROM THE
WEST SATURDAY AFTERNOON AND EVENING.  TIMING STILL LOOKS GOOD FOR
BRUNT OF SHOWERS/STORMS TO END EARLY SUNDAY MORNING.  FAVORED THE
SLIGHTLY WARMER HIGH TEMPS...MORE TOWARD A PERSISTENCE FORECAST THAN
CLIMO.

.LONG TERM...(SUNDAY THROUGH THURSDAY)...CD FNT PROGGED TO SHIFT SE
THRU FA EARLY SUN TAKING CHC SHRA/TSRA WITH IT. HOWEVER...BLENDED
SLGT/SMALL CHC POPS WITH GFE NEIGHBORS WHICH PROVIDES BUFFER IN THE
EVENT THAT FNT MOVES A LITTLE SLOWER. PERIOD OF COOLER/DRIER WX IN
STORE BEHIND THIS SYSTEM AS UPR TROF PROGRESSES E ACROSS THE GREAT
LAKES AND NERN U.S. WITH SFC RIDGE PRESSING E ACROSS THE MIDDLE
ATLANTIC STATES ON TUE. DRY REGIME EXTENDS BASICALLY THROUGH TUE
ALTHOUGH USED SLGT CHC POPS ACROSS THE MTNS AS NW FLO ENHANCES
OROGRAPHIC LIFT. INTRODUCED SMALL/SLGT CHC POPS ACROSS SW VA/NE TN
AND NRN CUMBERLAND PLATEAU FOR WED AND THEN ADDED AREA WIDE POP FOR
THU AS ANOTHER UPR TROF BUILDS E THRU THE NERN U.S. WITH IMPULSES
RIDING SE ACROSS CNTRL/SRN APPALACHIANS.

&&

.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN             63  88  64  82 /  20  20  20  60
KNOXVILLE MCGHEE TYSON AIRPORT, TN  62  85  64  81 /  20  20  20  60
OAK RIDGE, TN                       63  85  63  79 /  20  20  20  60
TRI CITIES AIRPORT, TN              57  82  57  79 /  30  30  20  50

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC......NONE.
TN......NONE.
VA......NONE.

&&

TG

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MORRISTOWN TN
555 AM EDT WED MAY 12 2005

NCZ060-061-TNZ012>018-035>047-067>074-081>087-098>102-VAZ001-002-005-
006-008-131100-
ANDERSON-BLEDSOE-BLOUNT SMOKY MTN-BRADLEY-CAMPBELL-CHEROKEE-
CLAIBORNE-CLAY-COCKE SMOKY MTN-EAST POLK-GRAINGER-HAMBLEN-HAMILTON-
HANCOCK-HAWKINS-JEFFERSON-JOHNSON-KNOX-LEE-LOUDON-MARION-MCMINN-
MEIGS-MORGAN-NORTH SEVIER-NORTHWEST CARTER-NORTHWEST COCKE-
NORTHWEST GREENE-NORTHWEST MONROE-NW BLOUNT-RHEA-ROANE-RUSSELL-
SCOTT TN-SCOTT VA-SEQUATCHIE-SEVIER SMOKY MTN-SOUTHEAST CARTER-
SOUTHEAST GREENE-SOUTHEAST MONROE-SULLIVAN-UNICOI-UNION-
WASHINGTON TN-WASHINGTON VA-WEST POLK-WISE-
555 AM EDT (455 AM CDT) WED MAY 12 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EAST TENNESSEE...SOUTHWEST
VIRGINIA AND EXTREME SOUTHWEST NORTH CAROLINA.

.DAY ONE (TODAY AND TONIGHT)...

A FRONTAL BOUNDARY WILL SAG SOUTH INTO NORTHEAST TENNESSEE LATER
TODAY AND WILL HELP INITIATE A CHANCE FOR AFTERNOON AND EVENING
THUNDERSTORMS ACROSS SOUTHWEST VIRGINIA AND NORTHEAST TENNESSEE.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN (FRIDAY THROUGH WEDNESDAY)...

ON SATURDAY A SHARP TROUGH WILL BRING A COLD FRONT TOWARD THE
TENNESSEE VALLEY AND SOUTHERN APPALACHIANS. STRONG THUNDERSTORMS
ARE POSSIBLE ALONG AND IN ADVANCE OF THE COLD FRONT. MOST OF THE
ACTIVITY WILL BE LATE IN THE DAY SO THE THREAT FOR SEVERE STORMS IS
STILL UNCERTAIN. THE COLD FRONT WILL MOVE EAST OF THE APPALACHIAN
MOUNTAINS EARLY SUNDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED SATURDAY NIGHT.

PLEASE STAY TUNED TO NOAA WEATHER RADIO OR VISIT OUR WEBSITE AT
WWW.SRH.NOAA.GOV/MRX.

TD