Severe Thunderstorm Warning 66, NWS Morristown, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
957 AM EDT FRI MAY 13 2005

.DISCUSSION...YESTERDAYS WEAK FRONTAL BOUNDARY IS DIFFICULT TO
LOCATE TO ME...BASED ON EITHER A WIND OR DEW POINT ANALYSIS.  UPPER
AIR PLOTS SHOW VERY WARM 850 MB TEMPS ACROSS OUR REGION WITH MAIN
BAROCLINIC ZONE FROM ERN OHIO VALLEY TO THE MID ATLANTIC STATES.
THUS...DONT EXPECT THE WEAK SURFACE BOUNDARY TO BE MUCH OF A FACTOR
TODAY...LEAVING TERRAIN TO BE THE MAIN FOCUS FOR CONVECTIVE
DEVELOPMENT.  PLOTS ALSO SHOW THAT THE UPPER RIDGE HAS SHIFTED JUST
TO OUR SE...ALLOWING SLIGHTLY BETTER STEERING WINDS FOR STORMS TODAY
WITH A N TO NE MOTION AROUND 10 KNOTS EXPECTED.

MODIFIED 12Z OHX AND RNK SOUNDINGS SHOW SLIGHT TO MODERATE
INSTABILITY WITH MAX TEMPS TOPPING OUT AGAIN WELL INTO THE 80S.
CAPES GENERALLY OF 1000 J/KG (RNK) TO PERHAPS AS HIGH AS 2500 J/KG
FOR MODIFIED OHX SOUNDING.  FREEZING/WET BULB ZERO HEIGHTS
RELATIVELY HIGH TODAY...AS IS THE EQUILIBRIUM LEVEL...SO SEVERE
THREAT LOOKS MINIMAL.  I MAY ADJUST THE POPS SLIGHTLY IN THE MORNING
UPDATE TO BE SURE TO HAVE CHANCE POPS IN ALL OF THE HIGHER TERRAIN
AREAS...WITH SOME WEAK CONVECTION ALREADY TRYING TO START IN THE SRN
MTNS.  PROBABLY WILL KEEP VALLEY/LOWER ELEVATIONS IN THE ISOLATED
CATEGORY OF POPS.

OTHERWISE...THINKING THAT PERSISTENCE ON MAX TEMPS TODAY IS A GOOD
BET.  AFTER PLOTTING YESTERDAYS HIGHS...MAY NUDGE MAX TEMPS UP A
FEW DEGREES IN MANY AREAS.  FULL UPDATE OF ZFP...GRIDS AND WEB
PRODUCTS BY 11 AM EDT.

&&

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

&&

TG

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MORRISTOWN TN
550 AM EDT FRI MAY 13 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-
550 AM EDT (450 AM CDT) FRI MAY 13 2005

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

.DAY ONE (TODAY AND TONIGHT)...

HIGH PRESSURE WILL DOMINATE THE REGION TODAY AND TONIGHT. THIS WILL
SOLAR HEATING TO FIRE UP A FEW THUNDERSTORMS, ESPECIALLY ALONG
RIDGES AND IN THE MOUNTAINS. SOME WILL LINGER INTO THE NIGHT.
MOVEMENT OF THE STORMS WILL BE PRETTY SLOW, AND SO SOME BRIEF HEAVY
RAIN MAY OCCUR WITH STORMS.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN (SATURDAY THROUGH THURSDAY)...

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 DURING THE TIME OF MAXIMUM HEATING
SO THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS. THE COLD FRONT
WILL MOVE EAST OF THE APPALACHIAN MOUNTAINS EARLY SUNDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED SATURDAY AND SATURDAY NIGHT.

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

BB