015  
FXUS64 KMRX 020532  
AFDMRX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MORRISTOWN TN  
1232 AM EST FRI DEC 2 2022  
   
..NEW AVIATION
 
 
   
UPDATE
 
 
ISSUED AT 1047 PM EST THU DEC 1 2022  
 
TEMPERATURES IN SOME LOCATIONS HAVE TRENDED COLDER, SO HOURLY AND  
FORECAST MINS HAVE BEEN ADJUSTED. OTHERWISE, FORECAST THROUGH THE  
MORNING IS STILL ON TRACK.  
 

 
   
SHORT TERM
 
 
(THIS EVENING THROUGH FRIDAY)  
ISSUED AT 336 PM EST THU DEC 1 2022  
KEY MESSAGES:  
 
1. DRY CONDITIONS REMAIN FOR THE SHORT TERM, WITH INCREASING CLOUDS  
THROUGHOUT THE DAY ON FRIDAY TO WRAP UP THE WORK WEEK.  
 
DISCUSSION:  
 
THE REMAINDER OF TODAY WILL BE DRY AS HIGH PRESSURE MIGRATES FROM  
OUR AREA NORTHEAST TOWARDS THE MID-ATLANTIC THIS AFTERNOON. HIGH  
CLOUDS WILL INCREASE THIS AFTERNOON AND OVERNIGHT WITH LOW TEMPS IN  
THE MID-20S TO MID-30S AREA WIDE. DRY AIR ALOFT MIXING DOWN TODAY  
RESULTS IN LOW DEWPOINTS AND SUBSEQUENTLY LOW RH VALUES, ESPECIALLY  
IN THE HIGHER ELEVATIONS. DEWPOINTS ARE IN THE TEENS ALREADY ACROSS  
MUCH OF EAST TN, WITH LOWER VALUES IN THE HIGHER TERRAIN.  
CONSEQUENTLY, THE RH VALUES DROP INTO THE TEENS AND 20S IN MANY  
PLACES AS WELL, WITH MUCH OF THE VALLEY SEEING RHS IN THE UPPER 20S  
TO MID 30S.  
 
CLOUD COVER INCREASES THROUGH THE DAY ON FRIDAY WITH WINDS VEERING  
TOWARD THE SOUTH, SLOWLY DRAWING MOISTURE BACK INTO THE AREA. CAPPED  
POPS AT LOW SLIGHT CHANCE FOR FRIDAY NIGHT SINCE I AM NOT EXPECTING  
MUCH IN THE WAY OF MEASURABLE PRECIPITATION GIVEN THE LACK OF  
NOTABLE FORCING AND DRY LOW LEVEL AIR ON FORECAST SOUNDINGS.  
 

 
   
LONG TERM
 
 
(FRIDAY NIGHT THROUGH NEXT THURSDAY)  
ISSUED AT 336 PM EST THU DEC 1 2022  
 
KEY MESSAGES:  
 
1. NEAR TO SLIGHTLY ABOVE NORMAL TEMPERATURES THROUGH THE EXTENDED,  
BUT SLIGHTLY BELOW NORMAL ON SUNDAY.  
 
2. STRONG SOUTHWESTERLY FLOW AT 850MB LATE FRIDAY INTO EARLY  
SATURDAY WILL PRODUCE GUSTY WINDS FOR THE HIGHER ELEVATIONS OF THE  
EAST TN MOUNTAINS, SOUTHWEST VA, AND THE NORTHERN CUMBERLAND PLATEAU.  
 
3. WET PATTERN SETS UP MONDAY THROUGH WEDNESDAY.  
 
DISCUSSION:  
 
FRIDAY NIGHT THROUGH SUNDAY  
 
WE START THE PERIOD WITH SOUTHWEST FLOW INCREASING OUT AHEAD OF AN  
APPROACHING COLD FRONT. 850 MB FLOW PEAKS AROUND 50KTS FRIDAY  
NIGHT/SATURDAY MORNING. WIND GUSTS FROM 40 TO 50 MPH ARE LIKELY  
ACROSS OUR HIGHER ELEVATIONS OF THE EAST TN MOUNTAINS, SOUTHWEST VA,  
AND THE NORTHERN CUMBERLAND PLATEAU AS NOTED BY THE HREF MEAN,  
WRF/ARW, AND THE NAM 3KM. IF THESE TRENDS HOLD, A WIND ADVISORY WILL  
BE NEEDED SOON. IN ADDITION TO THE WIND, SHOWERS WILL ACCOMPANY THE  
FRONT FRIDAY NIGHT INTO EARLY SATURDAY AFTERNOON. THEN, THE COLD  
FRONT WILL MOVE THROUGH AND WE DRY OUT BEHIND THE FRONT. SOUNDINGS  
SHOW LITTLE TO NO INSTABILITY SO WHILE A RUMBLE OR TWO OF THUNDER  
MAY OCCUR IT SHOULD MAINLY BE SHOWERS. PRECIP LOOKS TO BE ON THE  
LIGHTER SIDE WITH TOTAL QPF AVERAGING 0.25 INCHES ACROSS THE AREA.  
WE REMAIN DRY THROUGH SUNDAY MORNING BUT PRECIP CHANCES RETURN BY  
SUNDAY AFTERNOON/EVENING AS A WEAK SYSTEM MOVES ACROSS JUST TO OUR  
SOUTH.  
 
MONDAY THROUGH WEDNESDAY  
 
MODELS ARE STILL IN SOME DISAGREEMENT ON PRECIP TIMING DURING THIS  
PERIOD. HOWEVER, THE KEY TAKEAWAY SHOULD BE THAT SEVERAL INCHES OF  
RAINFALL ARE POSSIBLE DURING THIS TIMEFRAME. THE SETUP FOR THIS  
PATTERN IS AN AREA OF HIGH PRESSURE IN THE GULF OF MEXICO WITH  
MOISTURE STREAMING INTO OUR REGION FROM THE SOUTHWEST, AROUND THE  
WESTERN EDGE OF THE HIGH. PWATS IN EXCESS OF 1" WILL PRESENT AND  
WILL PEAK BETWEEN 1.2 AND 1.3 INCHES WHICH IS BETWEEN THE 90  
PERCENTILE AND MAX MOVING AVERAGE BASED ON BNA SOUNDING CLIMATOLOGY.  
CURRENT STORM TOTAL QPF FOR THIS PERIOD RANGES BETWEEN 2 TO 3  
INCHES. THESE VALUES COULD CHANGE DEPENDING ON WHERE THE HEAVIEST  
PRECIP AXIS SETS UP. DUE TO RECENT RAINFALL, WE WILL HAVE TO MONITOR  
FOR POTENTIAL FLOODING ACROSS AREAS THAT RECEIVE THE HEAVIER  
RAINFALL AMOUNTS. INSTABILITY REMAINS MOSTLY TO OUR SOUTH SO MAINLY  
SHOWERS WITH LITTLE TO NO THUNDER IN THE FORECAST. A COLD FRONT  
MOVES THROUGH WEDNESDAY NIGHT AND WE DRY OUT BEHIND THE FRONT  
 

 
   
AVIATION
 
 
(06Z TAFS)  
ISSUED AT 1222 AM EST FRI DEC 2 2022  
 
HIGH TO MID LEVEL CLOUDS ARE EXPECTED TO ADVECT INTO THE REGION  
AHEAD OF A SURFACE BOUNDARY THROUGHOUT TODAY. CIG HEIGHTS WILL  
GRADUALLY LOWER TONIGHT AND INTO THE END OF THE 6Z TAF PERIOD,  
WHERE BKN CLOUDS WILL BEGIN TO REACH HEIGHTS LOWER THAN 10KFT BUT  
SHOULD REMAIN VFR. CATEGORY CHANGES, ALONG WITH A MENTION OF  
PRECIP, WILL LIKELY NEED TO BE INTRODUCED IN THE NEXT ISSUANCE.  
SURFACE WINDS WILL BE OUT OF THE SOUTH TO SOUTHWEST.  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
CHATTANOOGA AIRPORT, TN 56 49 62 39 / 10 70 70 10  
KNOXVILLE MCGHEE TYSON AIRPORT, TN 58 47 60 36 / 10 70 70 0  
OAK RIDGE, TN 57 47 59 35 / 10 70 70 0  
TRI CITIES AIRPORT, TN 58 44 57 33 / 0 60 70 10  
 

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

 
 

 
 
SHORT TERM...WILLIAMS  
LONG TERM....SR  
AVIATION...KRS  
 
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