314
FXUS64 KMRX 182330
AFDMRX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
630 PM EST THU DEC 18 2025
..NEW AVIATION
KEY MESSAGES
UPDATED AT 628 PM EST THU DEC 18 2025
- WIND ADVISORY FOR STRONG MOUNTAIN WINDS; MEANWHILE WIDESPREAD
SHOWERS, AND ISOLATED THUNDER IN THE SOUTH ARE EXPECTED THIS
AFTERNOON INTO EARLY FRIDAY MORNING.
- COLDER TEMPERATURES BEHIND A FRONT ON FRIDAY, BUT REBOUND
QUICKLY OVER THE WEEKEND AND REMAIN MILD NEXT WEEK WITH MAINLY
DRY CONDITIONS.
DISCUSSION
ISSUED AT 1229 PM EST THU DEC 18 2025
SO FAR, WIND OBS IN THE MOUNTAINS HAVE NOT BEEN TOO IMPRESSIVE AND
UNDER ADVISORY CRITERIA, WITH EVEN COVE MOUNTAIN ONLY TOUCHING 40
MPH WITH THE LATEST OB. THE WINDS ARE EXPECTED TO INCREASE AS WE
GO THROUGH THE AFTERNOON, AS THE NAM SHOWS THE 850 MB LLJ AROUND
50 KT IN THE NEXT FEW HOURS, AND HREF PROBS OF 40+ KT GUSTS RISING
OVER A LARGER AREA ACROSS THE MOUNTAINS AND FOOTHILLS. CAN'T RULE
OUT AN ISOLATED GUST TO 55 MPH ON SOME MOUNTAIN PEAKS, BUT THE
PROBABILITY OF REACHING THIS HIGH IS LOW IN THE HREF. FOR THE TN
VALLEY, WE HAVE HAD A SURFACE INVERSION THIS MORNING THAT HAS BEEN
PREVENTING WINDS FROM REACHING THE GROUND AT MOST SPOTS. LOOKING
AT THE MODEL SOUNDINGS, THAT INVERSION LINGERS WELL INTO THE
EVENING UNTIL THE ARRIVAL OF A LINE OF SHOWERS. THE TIMING OF THIS
LINE APPEARS TO BE BETWEEN 03-07Z BASED ON THE CAMS. STRONGER
PORTIONS OF THE LINE COULD BRING WINDS ALOFT DOWN TO THE SURFACE,
WITH 40 TO 50 MPH GUSTS POSSIBLE. THERE IS SOME ELEVATED CAPE
TONIGHT, ENOUGH TO WARRANT A MENTION OF ISOLATED THUNDERSTORMS,
BUT NOT ENOUGH FOR A WIDESPREAD SEVERE THREAT. THE INTENSITY OF
THE LINE WILL BE DIMINISHING AS IT MOVES FROM THE CUMBERLAND
PLATEAU THROUGH THE TN VALLEY.
ON THE BACKSIDE OF THE SYSTEM EARLY FRIDAY MORNING, THE POTENTIAL
WINDOW FOR SNOW BETWEEN THE EXITING MOISTURE AND BUILDING COLD AIR
APPEARS TO CLOSE QUICKLY BEHIND THE SURFACE FRONT. THE UPPER
TROUGH FOLLOWS CLOSELY BEHIND THE FRONT, AND SO DRY AIR ALOFT BUILDS
IN RAPIDLY AND ENDS ANY PRECIP CHANCES BY SUNRISE FRIDAY MORNING.
COLDER TEMPERATURES FOLLOW THE STRONG COLD FRONT ON FRIDAY, WITH
HIGHS IN THE 40S. HIGHS REBOUND BACK TO THE 50S FOR SATURDAY AND
SUNDAY. A WEAK DISTURBANCE MAY BRING SOME LIGHT RAIN SATURDAY
NIGHT INTO SUNDAY BUT WITH LOW PROBABILITIES OF MEASURABLE
RAINFALL. HIGH TEMPS SHOULD BE MOSTLY IN THE 50S FOR NEXT WEEK.
THERE ARE SOME MORE WEAK DISTURBANCES SHOWN IN THE MODELS THAT
BRING LOW RAIN CHANCES NEXT WEEK, MAINLY TUESDAY-WEDNESDAY, BUT
THESE APPEAR TO HAVE LITTLE TO NO IMPACTS, IF THEY HAPPEN AT ALL.
THE GENERAL PATTERN LATE IN THE WEEK OF A LARGE RIDGE OVER TX/LA
WILL FAVOR DRY AND MILD CONDITIONS AROUND CHRISTMAS.
AVIATION
(00Z TAFS)
ISSUED AT 628 PM EST THU DEC 18 2025
MAIN WEATHER CONCERN IS LINE OF GUSTY SHOWERS MOVING THROUGH THE
REGION TONIGHT. MAIN TIMEFRAME FOR SHOWERS IS 02-08Z AHEAD OF A
COLD FRONT. CONDITIONS DROPPING TO IFR ARE EXPECTED UNDER THE
SHOWERS ALONG WITH BREEZY WINDS AHEAD OF THE LINE. ONCE THE LINE
MOVES THROUGH CEILINGS WILL REMAIN LOW THROUGH THE MORNING BEFORE
SLOWLY IMPROVING.
PRELIMINARY POINT TEMPS/POPS
CHATTANOOGA AIRPORT, TN 36 50 29 58 / 90 0 0 0
KNOXVILLE MCGHEE TYSON AIRPORT, TN 36 45 27 58 / 100 10 0 0
OAK RIDGE, TN 33 45 26 55 / 90 0 0 0
TRI CITIES AIRPORT, TN 36 42 25 56 / 90 10 0 0
MRX WATCHES/WARNINGS/ADVISORIES
NC...NONE.
TN...WIND ADVISORY UNTIL 4 AM EST FRIDAY FOR BLOUNT SMOKY MOUNTAINS-
COCKE SMOKY MOUNTAINS-JOHNSON-SEVIER SMOKY MOUNTAINS-
SOUTHEAST CARTER-SOUTHEAST GREENE-SOUTHEAST MONROE-UNICOI.
VA...NONE.
DISCUSSION...DGS
AVIATION...99
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