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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS64 KMRX 252008
AFDMRX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
308 PM EST WED FEB 25 2015

.SHORT TERM (TONIGHT THROUGH THURSDAY NIGHT)...
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A LOW LEVEL DRY LAYER IS DELAYING PRECIP AT THE GROUND OVER SOUTHERN
AREAS...BUT GRADUAL MOISTENING OF THIS LAYER SHOULD RESULT IN SNOW
BEGINNING NEAR CHATTANOOGA AROUND 22-23Z...WITH ACCUMULATIONS
STARTING AN HOUR OR TWO LATER AS TEMPERATURES DROP FROM EVAPORATIVE
COOLING. HEAVY TO MODERATE SNOWFALL IS EXPECTED AT TIMES THIS
EVENING AS AGEOSTROPHIC FORCING BETWEEN UPPER JET STREAKS PROVIDES
STRONG VERTICAL ASCENT. THIS LIFT APPEARS STRONGEST OVER SE TN...SW
NC..AND THE MOUNTAINS THIS EVENING. BY 06Z WE START TO SEE DRIER
AIR MOVING INTO SOUTHERN AREAS AT THE DENDRITE GROWTH LEVEL...AND
THE AREA OF BEST FORCING MOVES INTO NE TN AND SW VA. POPS WILL DROP
BACK TO A CHANCE NORTH TO SLIGHT CHANCE SOUTH BY EARLY THURSDAY
MORNING...WITH LITTLE TO NO ADDITIONAL ACCUMULATION EXPECTED AFTER
THIS TIME. THE WINTER STORM WARNING AND WINTER WEATHER ADVISORY
AREAS AND TIMING WILL REMAIN UNCHANGED.

A NW UPSLOPE FLOW AND SOME STEEPENING LAPSE RATES MAY KEEP SOME SNOW
SHOWERS AND FLURRIES IN NORTHERN AREAS AND THE MOUNTAINS THURSDAY
AFTERNOON AND NIGHT. IT DOES NOT APPEAR THAT THIS WILL ADD MUCH
ADDITIONAL SNOW ACCUMULATION TO THE TOTAL...AS UPSLOPE WINDS ARE
ONLY 10-15 KTS AND MOISTURE IS SHALLOW. FOR TEMPERATURES...WILL
UNDERCUT MOS GUIDANCE BY A FEW DEGREES TO ACCOUNT FOR THE SNOW
COVER...AND FOR THE EXPECTED OVERCAST CLOUD COVER THAT IS EXPECTED
TO LINGER THROUGH THURDAY.

.LONG TERM (FRIDAY THROUGH WEDNESDAY)...
A FEW AREAS OF LIGHT SNOW OR FLURRIES MAY LINGER OVER THE
EASTERN/NORTHEASTERN LOCATIONS FRIDAY MORNING BUT NO ADDITIONAL
ACCUMULATIONS ARE EXPECTED. OTHERWISE... SURFACE HIGH PRESSURE
BUILDS IN FRIDAY AND SATURDAY. WILL THEN SEE A PATTERN CHANGE
DEVELOP OVER THE REGION. WINDS BECOME SOUTHERLY ...CARRYING MUCH
WARMER AIR INTO THE TN VALLEY. WE WILL ALSO MOVE INTO AN UNSETTLED
PATTERN AS A SERIES OF LOWS PRESSURE SYSTEMS MOVE THROUGH THE
REGION FOR CHANCE TO LIKELY POPS SUNDAY THROUGH WEDNESDAY. THE MOST
SIGNIFICANT OF THESE SYSTEMS WILL MOVE THOUGH TUESDAY INTO TUESDAY
NIGHT. WEAK INSTABILITY IS EXPECTED TO NUDGE INTO SOUTHERN AREAS
AND ISOLATED THUNDERSTORMS WILL BE POSSIBLE...MIANLY NEAR THE CHA
AREA.
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&&

.PRELIMINARY POINT TEMPS/POPS...
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CHATTANOOGA AIRPORT, TN             28  40  24  37 / 100  10  10  10
KNOXVILLE MCGHEE TYSON AIRPORT, TN  28  37  22  33 / 100  30  10  10
OAK RIDGE, TN                       28  37  21  32 / 100  30  10  10
TRI CITIES AIRPORT, TN              27  35  21  29 / 100  40  10  10
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&&

.MRX WATCHES/WARNINGS/ADVISORIES...
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NC...WINTER STORM WARNING UNTIL 7 AM EST THURSDAY FOR CHEROKEE-CLAY.

TN...WINTER STORM WARNING UNTIL 7 AM EST THURSDAY FOR BLOUNT SMOKY
     MOUNTAINS-COCKE SMOKY MOUNTAINS-JOHNSON-SEVIER SMOKY
     MOUNTAINS-SOUTHEAST CARTER-SOUTHEAST GREENE-SOUTHEAST
     MONROE-UNICOI.

     WINTER WEATHER ADVISORY UNTIL 7 AM EST /6 AM CST/ THURSDAY FOR
     ANDERSON-BLEDSOE-CAMPBELL-CLAIBORNE-GRAINGER-HAMBLEN-
     HANCOCK-HAWKINS-JEFFERSON-KNOX-LOUDON-MORGAN-NW BLOUNT-
     NORTH SEVIER-NORTHWEST CARTER-NORTHWEST COCKE-NORTHWEST
     GREENE-RHEA-ROANE-SCOTT TN-SULLIVAN-UNION-WASHINGTON TN.

     WINTER STORM WARNING UNTIL 7 AM EST /6 AM CST/ THURSDAY FOR
     BRADLEY-EAST POLK-HAMILTON-MARION-MCMINN-MEIGS-NORTHWEST
     MONROE-SEQUATCHIE-WEST POLK.

VA...WINTER WEATHER ADVISORY UNTIL 7 AM EST THURSDAY FOR LEE-RUSSELL-
     SCOTT-WASHINGTON-WISE.
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&&

$$

DGS/MJB