Severe Thunderstorm Warning 356, NWS Morristown, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
300 PM EDT THU AUG 21 2003

THE FOLLOWING ARE THE FORECAST DISCUSSIONS FROM THE PAST 24 HOURS...
WITH THE MOST RECENT FIRST. THIS PROVIDES A HISTORY OF THE
DEVELOPMENT OF THE CURRENT FORECAST.
*********************************************************************
AFTERNOON FORECAST DISCUSSION
300 PM EDT THU AUG 21 2003

SHORT TERM...WITH ABUNDANT LOW LEVEL MOISTURE AND A WEAKLY UNSTABLE ATMOSPHERE
IN PLACE...SCATTERED SHOWERS/THUNDERSTORMS HAVE DEVELOPED ACROSS THE AREA.  THE
CONVECTION WILL CONTINUE THOUGH THE OVERNIGHT HOURS WITH ANOTHER ROUND EXPECTED
FRIDAY AFTERNOON/EVENING IN ADVANCE OF AN APPROACHING COOL FRONT.  THE FRONTAL
PASSAGE WILL MOVE THROUGH EARLY SATURDAY MORNING WITH A DRIER...MORE STABLE AIR
MASS MOVING IN BEHIND THE FRONT.

CHA   71  90  71  88 /  30  40  30  30
TYS   71  88  69  86 /  40  40  40  30
TRI   68  84  67  82 /  40  40  40  30
OQT   71  88  69  86 /  40  40  40  30

.MRX...
NC...NONE.
TN...NONE.
VA...NONE.

MJB
*********************************************************************
MID-MORNING FORECAST DISCUSSION
930 AM EDT THU AUG 21 2003

WITH PLENTIFUL LOW LEVEL MOISTURE AND A WEAKLY UNSTABLE AIR MASS IN PLACE...
THE MORRISTOWN FORECAST AREA WILL CONTINUE TO SEE SCATTERED SHOWERS AND
THUNDERSTORMS THIS AFTERNOON AND EVENING.  SHOWER/THUNDERSTORM ACTIVITY WILL
BECOME MORE WIDESPREAD ON FRIDAY EVENING IN ADVANCE OF A COOL FRONT THAT IS
PROGGED INTO THE AREA EARLY SATURDAY.  ALL LOOKS GOOD IN CURRENT FORECAST WILL
UPDATE TO REMOVE MORNING WORDING ONLY.

.MRX...
NC...NONE.
TN...NONE.
VA...NONE.

MJB

*********************************************************************
EARLY MORNING FORECAST DISCUSSION
415 AM EDT THU AUG 21 2003

LITTLE CHANGE TO CURRENT FORECAST. UPPED POPS FOR FRIDAY EVENING
AND SAT MORNING. WENT A LITTLE COOLER SUN NIGHT.

WEAK FLOW AND RELATIVELY DRY AIRMASS CONTINUES ALOFT WITH DECENT LLVL MOISTURE
ACROSS AREA. BEST LLVL MOISTURE ABOUT HALF WAY NE UP CWA AND WILL INCH
NORTHWARD SOME TODAY. CLOSE REPEAT OF WEDNESDAY. COLD FRONT MOVES SOUTH INTO
KENTUCKY ON FRIDAY. PREFRONTAL ENVIRONMENT BECOMES QUIT UNSTABLE BY FRIDAY
AFTERNOON. DIURNAL SCT CONVECTION EXPECTED. FAVORABLE STORM MOTIONS AND UPPER
DIFFLUENCE SHOULD ENABLE CONVECTIVE LINES TO MOVE INTO AREA FROM NORTH BY FRI
EVENING. MODELS AGGRESSIVE IN MOVING FRONT THROUGH AREA BY EARLY SATURDAY. TOOK
A SLOWER APPROACH FOR NOW WITH LINGERING PCPN EARLY SAT MAINLY SOUTH. GFS
DEPICTS FAIRLY STRONG SHORT WAVE DIVING DOWN FROM THE NW ON SAT WHICH SHOULD
HOLD UP THE FRONTAL BOUNDARY INTO THE AFTN. PRETTY GOOD COOLING EARLY NEXT WEEK
ESPCLY IN THE MNTS.

CHA BB 091/070 091/070 086 17334
    BAABB 066/085 066/085 065/084 068/084 068 55221111111
TYS BT 090/070 088/068 085 17336
    BAABB 064/084 063/084 063/084 067/084 067 63211111111
TRI BT 087/066 084/065 083 17336
    BAABB 060/082 060/082 059/082 063/083 063 63111111111
OQT BT 090/071 089/068 085 17336
    BAABB 064/084 063/084 063/084 067/084 067 63211111111=

SON
*********************************************************************
EVENING FORECAST DISCUSSION (UPDATE)
1010 PM EDT WED AUG 20 2003

RADAR CONTINUES TO SHOW WIDELY SCATTERED SHOWERS AND THUNDERSTORMS
ACROSS THE SOUTHERN TWO-THRIDS OF THE FORECAST AREA. BNA EVENING
SOUNDING SHOWS A VERY UNSTABLE AIRMASS AND CURRENT MSAS DEPICTS
LIFTED INDICES OF -4 TO -5 OVER THE CENTRAL AND SOUTHERN SECTIONS.

WILL CONTINUE TO WATCH COVERAGE OF STORMS...BUT MAY HAVE TO KEEP
A MENTION OF ISOLATED THUNDERSTORMS FOR TYS SOUTHWARD FOR THE
REST OF THE NIGHT.

CURRENT FORECAST LOWS LOOK GOOD.

DH
*********************************************************************
AFTERNOON FORECAST DISCUSSION
300 PM EDT WED AUG 20 2003

STILL EXPECT THE POSSIBILITY FOR SOME ISOLATED TO SCATTERED SHOWERS
TO DEVELOP...MAINLY OVER THE SOUTHERN PORTIONS OF THE FORECAST AREA.
WILL MAINTAIN SLIGHT CHANCE EVENING POPS ACROSS THE SOUTHERN THIRD
OF THE FORECAST AREA.

FOR THURSDAY...MODELS SHOW HIGH CONTINUING TO DOMINATE THE WEATHER
MID-LEVEL CAP WILL CONTINUE TO LIMIT DEVELOPMENT...BUT FEEL AREA
TERRAIN WILL ALLOW WIDELY/SCATTERED THUNDERSTORMS TO DEVELOP.  SOME
OF THE STORMS WILL MOVE INTO THE VALLEY LATE IN THE DAY. WILL
MAINTAIN BEST POPS ACROSS CHA AREA WITH GENERALLY DRY FORECAST FOR
TRI. FEEL PERSISTENCE IS BEST TEMPERATURE FORECAST.

EXTENDED...LOW LEVEL MOISTURE AND WEAK INSTABILITY WILL KEEP AT
LEAST A SLIGHT CHANCE OF SHOWERS/THUNDERSTORMS ACROSS THE AREA
THROUGH FRIDAY.  HOWEVER...THE BEST CHANCE OF CONVECTIVE DEVELOPMENT
WILL BE EARLY SATURDAY AS THE TAIL END OF A COOL FRONT TRACKS
ACROSS THE AREA.  A RIDGE OF HIGH PRESSURE BUILDS IN BEHIND THE FRONT
SO FOR DRY CONDITIONS THROUGH THE REMAINDER OF THE TIME FRAME.

HW/MJB

CHA   72  92  71  90 /  30  40  40  30
TYS   71  90  69  88 /  20  30  30  30
TRI   66  88  66  86 /  10  30  30  30
OQT   71  90  69  88 /  20  30  30  30

NCZ060-061-TNZ012>018-035>047-067>074-081>087-098>102-VAZ001-002-005-
006-008-221100-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MORRISTOWN TN
542 AM EDT THU AUG 21 2003

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

.DAY ONE (TODAY)...

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...

A COLD FRONT WILL BE MOVING SOUTHEAST THROUGH KENTUCKY TOWARDS THE
TENNESSEE VALLEY FRIDAY EVENING. INCREASING UPPER LEVEL MOISTURE AND
LIFT DURING THE AFTERNOON HOURS WILL CAUSE THUNDERSTORMS TO DEVELOP
AHEAD OF THE FRONT BY EVENING. STRONG TO POSSIBLY SEVERE
THUNDERSTORMS MAY DEVELOP BY EVENING MAINLY ACROSS SOUTHWEST
VIRGINIA AND NORTHEAST TENNESSEE. HAZARDOUS WEATHER IS POSSIBLE AT
THAT TIME.

.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION MAY BE REQUIRED LATE FRIDAY AFTERNOON AND EVENING
ACROSS SOUTHWEST VIRGINIA AS WELL AS EAST CENTRAL AND NORTHEAST
TENNESSEE.

STAY TUNED OR VISIT OUR WEBSITE AT WWW.SRH.NOAA.GOV/MRX.

TD