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Area Forecast Discussion
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FXUS64 KMRX 180737
AFDMRX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
337 AM EDT SAT MAY 18 2013

.SHORT TERM...-- Changed Discussion --(TODAY THROUGH SUNDAY NIGHT)...THE MAIN WEATHER
FEATURE WILL BE WEAKENING UPPER TROUGH OVER THE TENNESSEE VALLEY
AND SOUTHERN APPALACHIANS. PERIODS OF SHOWERS AND AFTERNOON AND
EVENING THUNDERSTORMS WILL CONTINUE TODAY THROUGH SUNDAY.
INSTABILITY BECOMES A LITTLE BETTER SUNDAY AS A LITTLE MORE
INSOLATION ANTICIPATED. WILL CONTINUE WITH LIKELY POPS THROUGH MOST
OF THE PERIOD. AREA RAINS AND CLOUDS SLOWLY DIMINISHING THROUGH THE
PERIOD WILL ALLOW FOR RADIATIONAL FOG DEVELOPMENT FOR SATURDAY AND
SUNDAY NIGHTS. WOULD NOT BE SUPRISED TO SEE LOCALLY DENSE FOG.

AS FOR TEMPERATURES FOLLOWED A BLEND OF MET AND GFS MOS..WHICH HAS
WORKED BEST THE PAST COUPLE DAYS.

.LONG TERM (MONDAY THROUGH FRIDAY)...UPPER LEVEL SHORTWAVE RIDGING
WILL OCCUR ON MONDAY WITH CHANCES OF THUNDERSTORMS FOCUSED ON THE
HIGHER TERRAIN OF THE MOUNTAINS OF NE TN AND SW VA. SOUTHERLY LOW
LEVEL FLOW WILL PROVIDE ABUNDANT LOW LEVEL MOISTURE BY TUESDAY. THE
UPPER TROUGH OVER THE NORTHERN PLAINS REMAINS NEARLY STATIONARY
THROUGH WEDNESDAY. THE ASSOCIATED FRONT WILL BE ACROSS WEST
TENNESSEE WEDNESDAY BUT SEEMS TO LOSE ITS IDENTITY BY THURSDAY. THE
MORE DEFINED FRONTAL BOUNDARY WILL BE ACROSS THE NORTHERN OHIO
VALLEY. THE GFS SLOWLY BRINGS THE COOLER AIR INTO THE REGION
SOMETIME FRIDAY WHILE THE ECMWF IS ABOUT 24 TO 36 HOURS SLOWER.
ADDITIONALLY THE ECMWF IS MUCH LESS AMPLIFIED WITH ITS HANDLING OF
THE MID-WEEK UPPER TROUGH AS IT TRACKS IT INTO THE GREAT LAKES
REGION RATHER THAN OVER THE SOUTHERN OHIO VALLEY. WEDNESDAY THROUGH
THURSDAY LOOK LIKE THE BEST CHANCES OF SHOWERS AND THUNDERSTORMS FOR
THIS TIME PERIOD. TEMPERATURES EARLY IN THE WEEK WILL BE WELL ABOVE
NORMAL AND SLOWLY TREND TOWARDS NORMAL BY THE END OF THE WEEK.-- End Changed Discussion --

.PRELIMINARY POINT TEMPS/POPS...
-- Changed Discussion --CHATTANOOGA AIRPORT, TN 79 64 83 64 89 / 80 60 50 20 10
KNOXVILLE MCGHEE TYSON AIRPORT, TN 77 62 83 63 87 / 90 60 60 30 10
OAK RIDGE, TN 76 63 82 63 87 / 90 60 60 30 10
TRI CITIES AIRPORT, TN 75 58 80 58 85 / 90 70 70 40 10-- End Changed Discussion --

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

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