Severe Thunderstorm Warning 218, NWS Morristown, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
300 PM EDT SUN AUG 18 2002

THE FOLLOWING ARE ALL THE FORECAST DISCUSSIONS FROM THE PAST 24
HOURS...WITH THE MOST RECENT ON TOP. THIS PROVIDES A HISTORY OF THE
DEVELOPMENT OF THE CURRENT FORECAST.
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AFTERNOON FORECAST DISCUSSION
300 PM EDT SUN AUG 18 2002

THUNDERSTORMS/SHOWERS POPPING OVER MIDDLE TN TO CUMBERLAND PLATEAU.
CONSOLIDATING INTO A SOLID LINE AT LEADING EDGE. TODAYS POPS GOOD.
THESE WILL MOVE THROUGH THE ENTIRE CWA FROM WEST TO EAST AND DROP
MUCH NEEDED RAIN ON MOST PLACES. EXACT TOTALS UP IN THE AIR.

WE STILL SIT AHEAD OF THE WEAKENING FRONT TO THE NORTHWEST. MODELS
WEAKEN FRONT STILL FURTHER UNTIL ITS A SHADOW OF ITS FORMER SELF
BY ITS ARRIVAL MONDAY NIGHT. IT WILL SWEEP THROUGH THE REGION
KEEPING A CHANCE FOR CONVECTION THROUGH MONDAY NIGHT. HAVE REMOVED
ALL MENTION OF PRECIP FOR TUESDAY THROUGH THURSDAY DUE TO DEEP
DRYING AND BUILDING OF RIDGE (REMOVAL OF UPPER SUPPORT). NOT TO
SAY THAT AN ISOLATED SHOWER WONT FIRE SOMEWHERE IN THE SUNSHINE, SO
LEFT 10 POP IN REVISED DIGITAL FORECAST.

TEMPS AND WINDS LOOK BUT DID TWEAK WIND DIRECTIONS A BIT TO ACCOUNT
FOR SLIGHT WIND SHIFT WHEN FRONT MEANDERS ACROSS REGION. DONT
BELIEVE FOG WILL WARRANT PLACEMENT IN FORECAST.

LATER ON IN EXTENDED...ANOTHER FRONT COMES ON FRIDAY-SATURDAY.
MODELS DEPICT IT MORE STRONGLY THAN THIS ONE. HOWEVER...IT MIGHT
BECOME WEAKER AS THE WEEK PROGRESSES. STILL...PUT SLIGHT CHANCE
IN FRIDAY AND CHANCE ON SATURDAY. BACK TO PARTLY CLOUDY SUNDAY,
WHICH WAS A LITTLE DIFFICULT TO DECIDE, BUT SO FAR OUT AND WITH THE
MOISTURE AND DYNAMICS A LITTLE SO-SO WENT WITH CONSERVATIVE WORDING.

FOLLOWING FORECAST ARE PRELIMINARY:

CHA   71  91  69  90 /  30  30  30  10
TYS   69  89  67  89 /  30  30  30  10
TRI   66  86  64  87 /  30  30  30  10
OQT   69  88  67  88 /  30  30  30  10

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

BB

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LATE MORNING FORECAST DISCUSSION
940 AM EDT SUN AUG 18 2002

WILL UPDATE ZONES TO REMOVE MORNING FOG WORDING.  WILL LEAVE POPS AS
IS WITH CONVECTION ALREADY TAKING PLACE IN SE TN AND SOLAR HEATING
ON TRACK TO FIRE THINGS UP.

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

BB

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MORNING FORECAST DISCUSSION
330 AM EDT SUN AUG 18 2002

FRONT ACROSS THE OHIO VALLEY REMAINS NEARLY STATIONARY WITH GOOD
SOUTHWEST FLOW CONTINUING AT ALL LEVELS OVER THE NEXT FEW DAYS.  THE
FRONT WILL SLOWLY SAG SOUTH AND BE NEAR THE FORECAST AREA LATE
MONDAY OR EARLY TUESDAY.  SCATTERED SHOWERS WILL CONTINUE INTO
TUESDAY.

MODELS VERY CLOSE AS IS GUIDANCE NUMBERS.  ONLY MINOR DEVIATION FROM
A BLEND FORECAST OF NGM...AVN FORECAST NUMBERS.

CHA   90  70  91  71 /  50  30  30  20
TYS   88  69  90  70 /  50  30  30  20
TRI   87  66  88  67 /  50  30  30  20
OQT   88  69  90  70 /  50  30  30  20

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

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EVENING FORECAST DISCUSSION
900 PM EDT SAT AUG 17 2002

SHOWERS AND ISOLATED THUNDERSTORMS HAVE MOVED EAST AND NORTHEAST OUT
OF THE FORECAST AREA THIS EVENING AS THE SUN HAS SET. BEST
INSTABILITY AHEAD OF COLD FRONT APPROACHING THE OHIO VALLEY LIES TO
THE NORTHWEST AND WEST OVER KENTUCKY AND WEST TENNESSEE. WEAK
VORTICITY LOBE WILL MOVE NORTHEAST OUT OF MS AND NORTH AL INTO
MIDDLE TN OVERNIGHT AND EARLY SUNDAY. WITH REDEVELOPMENT POSSIBLE
SOUTHWEST AND WEST OF THE FORECAST AREA RELUCTANT TO TAKE OUT SLIGHT
CHANCE FOR FEAR SHOWERS AND A POSSIBLE THUNDERSTORM WILL MOVE IN
LATER. UPDATE TO DECREASE WINDS.

TD