560  
FXUS64 KMRX 161059 AAA  
AFDMRX  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE MORRISTOWN TN  
659 AM EDT TUE SEP 16 2025  
   
..NEW AVIATION
 
 
   
DISCUSSION
 
 
ISSUED AT 132 AM EDT TUE SEP 16 2025  
 
KEY MESSAGES:  
 
1. ISOLATED TO SCATTERED SHOWERS AND STORM CHANCES TODAY(20-45%),  
WITH DRY CONDITIONS THE REMAINDER OF THE WEEK.  
 
2. MOSTLY SEASONABLE TEMPERATURES TUESDAY AND WEDNESDAY BECOMING  
INCREASINGLY ABOVE NORMAL WITH HIGHS IN THE UPPER 80S TO LOW 90S  
FOR THE LATTER HALF OF THE WEEK.  
 
DISCUSSION:  
 
AN UPPER LOW REMAINS CENTERED NEAR THE NORTH & SOUTH CAROLINA  
BORDER. THE CYCLONIC FLOW IS PROMOTING ADVECTION OF MID TO HIGH  
LEVEL CLOUDS ATOP THE FORECAST AREA, ESPECIALLY EAST OF I75, AND  
WILL HELP LIMIT PATCHY FOG COVERAGE DUE TO POOR RADIATIONAL  
COOLING CONDITIONS. OVERALL, RATHER QUIET AS WE HEAD THROUGH THE  
EARLY AM HOURS OUTSIDE OF PERHAPS AN OCCASIONAL SHOWER.  
 
PRECIPITATION CHANCES WILL GRADUALLY INCREASE(20-45%) LATE MORNING  
INTO THE PM HOURS AS A SUBTLE IMPULSE TRAVERSES MEAN FLOW ALOFT. THE  
GREATEST PRECIP CHANCES WILL GENERALLY BE ALONG THE CUMBERLAND  
PLATEAU, E TENNESSEE MOUNTAINS, AND IN VICINITY OF THE I-75  
CORRIDOR. LATEST RAP AND NAMBUFR SOUNDINGS SUGGEST MLCAPE WILL BE  
BETWEEN 500-1000J/KG WITH WEAKER MID-LEVEL LAPSE RATES IN THE SOUTH  
SIDE OF 6C/KM. NO SIG WEATHER IS EXPECTED DUE TO THE MARGINAL AT  
BEST THERMO PROFILE, THOUGH, EFFECTIVE BULK SHEAR NEAR 15-20KTS MAY  
AID IN THE DEVELOPMENT OF A FEW THUNDERSTORMS.  
 
THE CENTER OF THE CLOSED UPR LOW WILL LIFT NORTHEASTWARD AND  
EVENTUALLY DISSOLVE WEDNESDAY INTO THURSDAY. A PRECIP FREE  
FORECAST RETURNS AS TEMPERATURES BEGIN TO SLOWLY TREND FROM  
SEASONABLE VALUES TO A FEW DEGREES ABOVE NORMAL, ESPECIALLY AS  
SHORTWAVE RIDGING BECOMES MORE PROMINENT BY FRIDAY AND SATURDAY.  
BY THIS TIME PORTIONS OF THE SOUTHERN VALLEY MAY EVEN SEE HIGH  
TEMPERATURES ENCROACH INTO THE LOW 90S.  
 
DETERMINISTIC LONG RANGE MODELS LACK AGREEMENT ON THE  
POSITION/AMPLITUDE OF A POTENTIAL POSITIVELY TILTED SHORTWAVE TROUGH  
FOR THE LATTER HALF OF THE WEEKEND INTO EARLY NEXT WEEK. POPS MAKE A  
RETURN AREA WIDE BUT CONFIDENCE IS LOW THIS FAR OUT, THUS, GENERALLY  
LIMITED TO 30% OR LESS.  
 

 
   
AVIATION
 
 
(12Z TAFS)  
ISSUED AT 647 AM EDT TUE SEP 16 2025  
 
SCATTERED TO BROKEN MIDLEVEL CLOUD COVER IS EXPECTED THROUGH  
TODAY, WITH NO AVIATION IMPACTS. THERE MAY BE SOME ISOLATED  
SHOWERS AROUND THE AREA THIS AFTERNOON, BUT THE CHANCE OF ONE AT  
THE TERMINALS IS TOO LOW AT THIS TIME TO WARRANT A MENTION IN THE  
TAFS.  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
CHATTANOOGA AIRPORT, TN 86 64 88 63 / 20 10 10 0  
KNOXVILLE MCGHEE TYSON AIRPORT, TN 82 62 83 61 / 20 10 0 0  
OAK RIDGE, TN 82 61 83 60 / 20 10 0 0  
TRI CITIES AIRPORT, TN 78 57 79 57 / 20 10 10 0  
 

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

 
 

 
 
DISCUSSION...KRS  
AVIATION...DGS  
 
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