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000
FXUS64 KMRX 062049
AFDMRX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
347 PM EST FRI DEC 6 2013

.SHORT TERM (TONIGHT AND SATURDAY)...
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SHALLOW COLD FRONT HAS HUGGED
THE SOUTHERN APPALACHIANS THIS MORNING. STRONG LOW LEVEL INVERSION
FROM ~1400-3000 FEET WEST OF THE COLD FRONT. THIS FEATURE IS
TRAPPING STRATUS CLOUDS ACROSS THE EAST TN VALLEY TODAY. TAIL END OF
STRENGTHENING UPPER JET WILL MOVE EAST THROUGH THE TN VALLEY
TONIGHT. RIGHT ENTRANCE REGION OF JET WILL ENHANCE LIFT AND AID IN
THE DEVELOPMENT OF ELEVATED CONVECTION BETWEEN FRONT AND UPPER JET.
BEST CHANCES FOR CONVECTION WILL BE BETWEEN 9PM AND 1 AM. MOST AREAS
SHOULD SEE AN ADDITIONAL INCH OF RAINFALL. COLDER AIR BEGINS
FILTERING IN OVERNIGHT. SOME MIXED PRECIPITATION WILL LIKELY OCCUR
ON BACK SIDE OF PRECIPITATION. RELATIVELY HIGH FREEZING LEVEL WILL
DROP DOWN TO AROUND 1500 FEET BY DAY BREAK. AREAS ALONG THE
CUMBERLAND PLATEAU...SOUTHWEST VIRGINIA AND PORTIONS OF NE TN MAY
SEE SOME LIGHT ICE ACCRETION PRIMARILY ALONG TREE LIMBS AND POWER
LINES. CONDITIONS SHOULD CLEAR OUT BY SATURDAY AFTERNOON WITH SOME
HIGH CLOUDINESS IN UPPER SW FLOW. TONIGHT TEMPERATURE WILL BE NEAR
STEADY OR FALL SLOWLY WITH COOLER TEMPERATURES IN THE SATURDAY
MORNING HOURS. AFTERNOON HIGHS WILL REMAIN COOL...MAINLY IN THE
40S.

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...STILL LOOKING TO THIS
NEXT SYSTEM THAT WILL MOVE INTO THE AREA SATURDAY NIGHT AND WILL
CONTINUE WITH PRECIPITATION THROUGH MONDAY...THEN START TO TAPER OFF.

THERE ARE SEVERAL CONCERNS/ITEMS OF INTEREST....WILL BREAK THEM DOWN
HERE...

1...WILL THERE BE ANY FREEZING PRECIP ON THE FRONT SIDE OF THIS
SYSTEM SATURDAY NIGHT AS THE PRECIPITATION OVERSPREADS A COLD/COOL
AIR MASS?  ONLY SMALL AMOUNTS...THINK THAT MOST FAVORED AREAS ARE IN
THE NORTHWARD DRAINING BASINS...NORTHERN CAMPBELL AND SCOTT COUNTIES
IN TN...AROUND THE TOWN OF THE JELLICO...AND NORTHERN WISE COUNTY IN
VA...WHERE NORTHEAST SURFACE WINDS WILL TRAP COLD AIR IN THESE
VALLEYS.  RIGHT NOW LOOKS LIKE LITTLE IF ANY IMPACT...AND FOR IMPACT
IT WOULD BE VERY LOCALIZED.

2...WILL THERE BE FLOODING RAINS DURING THIS LONG
DURATION...SATURDAY NIGHT THROUGH MONDAY?  ANY FLOODING DURING THIS
PERIOD SHOULD BE LIMITED.  EXPECTED AMOUNTS ARE ONLY BETWEEN 1-2
INCHES...1 INCH EAST AND 2 INCHES WESTERN AREAS...AND THIS IS SPREAD
OVER A PERIOD OF TWO DAYS.  HOWEVER...THE OVERALL 4-5 DAY TOTALS MAY
CAUSE SOME MINOR FLOODING OF LARGER STREAMS...RIVERS...AND OTHER
FLOOD-PRONE LOW-LYING AREAS.

3...WILL THERE BE A MOUNTAIN WAVE HIGH WIND EVENT SUNDAY AND SUNDAY
NIGHT?  RIGHT NOW...THIS LOOKS TO BE A VERY MINIMAL WIND EVENT.  THE
WINDS ARE NOT OVERLY STRONG AND ALSO ALIGN PRETTY QUICKLY WITH THE
SPINE OF THE MOUNTAINS...WHEREAS IN GOOD WIND EVENTS...THE WINDS ARE
FROM THE SOUTH OR SOUTHEAST CROSSING THE MOUNTAINS.

4...WILL THERE BE THUNDER DURING THE WARM ADVECTION PHASE SUNDAY
THROUGH MONDAY?  LOOKS LIKE MOST OF THE THUNDER WILL STAY SOUTH OF
THE AREA...WILL NOT MENTION THUNDER IN THE FORECASTS FOR SUNDAY
THROUGH MONDAY.

5...WILL THE BACK SIDE OF ALL THIS PRECIP HAVE ANY MEANINGFUL WINTRY
PRECIPITATION ON MONDAY NIGHT THROUGH TUESDAY?  RAIN SHOWERS WILL BE
TURNING TO SNOW SHOWERS AS THE COLDER AIR MOVES IN.  THERE IS A
LITTLE MORE MOISTURE IN THE FLOW THAT COULD ENHANCE THE POSSIBILITY
OF A MEASURABLE SNOW...ESPECIALLY IN THE MOUNTAINS FOR LATE MONDAY
NIGHT AND INTO TUESDAY...STILL A LITTLE EARLY TO DEFINE THIS.

6...HOW COLD WILL THE TEMPERATURES BE NEXT WEEK?  LOOKS PRETTY
COLD...BUT NOT AS COLD AS IT DID IN YESTERDAY`S MODELS.

7...WHEN THE NEXT SYSTEM COMES IN FOR LATE NEXT WEEK...WILL THERE BE
ANY WINTRY PRECIPITATION?  WHEN THIS SYSTEM COMES IN...THE MODELS
AGREE THAT THE WARMER AIR AND MOISTURE WILL COME INTO THE AREA
TOGETHER...THEREBY MINIMIZING THE CHANCES FOR WINTER PRECIPITATION.






THERE ARE TWO ISSUES WITH THIS NEXT WAVE OF PRECIPITATION...FIRST IS
THE THREAT FOR ANY FREEZING/FROZEN PRECIPITATION THROUGH ABOUT 15Z
SUNDAY...WHEN THE WARMER AIR SHOULD WIN-OUT...AND THE SECOND ISSUE
IS HOW HEAVY THE RAIN WILL GET.

THE PATTERN PRETTY MUCH STAYS UNSETTLED FOR THE FIRST 3 DAYS OF THIS
PERIOD...UNTIL THE TROUGH AXIS FINALLY CLEARS THE AREA...ROUGHLY
LATE TUESDAY.  SO FROM 00Z WED THROUGH THE END OF THE FORECAST WILL
KEEP IT DRY.

GETTING BACK TO SATURDAY NIGHT...LOOKS LIKE MOST OF THE AREA WILL
JUST GET A COLD RAIN...BUT CONCERNED ABOUT NORTHWESTERN AREAS THAT
WILL HAVE UPSLOPE NORTHERLY LOW LEVEL FLOW...SUCH AS JELLICO AND
ONEIDA...THAT THE COLD AIR MASS MAY BE LOCKED INTO PLACE LONGER AND
THERE WILL BE A BETTER CHANCE OF FREEZING RAIN...BUT ONLY EXPECTING
A FEW HUNDREDTHS OF ACCRUAL...SO AT THIS TIME...NOT ANTICIPATING
MANY PROBLEMS.  ALSO AM MENTIONING PARTS OF WISE AND RUSSELL VA
COUNTIES FOR LIGHT FREEZING RAIN...BUT PRECIP SHOULD BE LIGHTER
THERE OVERNIGHT.

FOR SUNDAY THROUGH MONDAY NIGHT...PRECIP SHOULD BE RAIN...THEN AS
COLD AIR RETURNS ON TUESDAY...WILL LIKELY HAVE SOME SNOW SHOWERS ON
THE BACK END OF THE SYSTEM.

IN THE SECOND WAVE OF PRECIP...FROM SATURDAY NIGHT THROUGH
SUNDAY...WE HAVE PRECIP OF ABOUT 1/2 INCH TO AN INCH ACROSS THE
AREA.  THERE WILL BE MORE RAIN ON MONDAY...THAT WILL BE ADDRESSED IN
FUTURE FORECASTS.
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&&

.PRELIMINARY POINT TEMPS/POPS...
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CHATTANOOGA AIRPORT, TN             37  46  40  47  45 / 100  10  90 100  90
KNOXVILLE MCGHEE TYSON AIRPORT, TN  38  44  36  46  43 / 100  20  80  90  90
OAK RIDGE, TN                       35  43  35  44  42 / 100  10  80  90  90
TRI CITIES AIRPORT, TN              38  41  34  46  37 / 100  20  80  80  90
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&&

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

&&

$$

SON/GM