366  
FXUS64 KMRX 291253 AAA  
AFDMRX  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE MORRISTOWN TN  
ISSUED BY NATIONAL WEATHER SERVICE NASHVILLE TN  
853 AM EDT THU MAY 29 2025  
   
..NEW UPDATE
 
 
   
UPDATE
 
 
ISSUED AT 840 AM EDT THU MAY 29 2025  
 
QUICK UPDATED TO INCREASE THE CHANCE OF SHOWERS AND POSSIBLY  
THUNDERSTORM ACROSS THE PLATEAU AND SOUTHEAST TENNESSEE. A SHORT-  
WAVE WILL MOVE ACROSS THE GULF COAST STATES AND TENNESSEE VALLEY  
PRODUCING PERIODS OF CONVECTION. THE GREATEST COVERAGE WILL BE  
NEAR THE TERRAIN FEATURES. INSTABILITY WILL BE MARGINAL WITH CAPES  
OF 1000 WITH LITTLE TO NO SHEAR. GENERALLY A FAIRLY SATURATED  
VERTICAL PROFILE. STRONG TO SEVERE STORMS ARE NOT EXPECTED.  
 
GIVEN THE MOSTLY CLOUDY SKY AND PERIODS OF CONVECTION HAVE LOWERED  
HIGH TEMPERATURES MOST LOCATIONS.  
 

 
   
SHORT TERM
 
 
(TONIGHT THROUGH FRIDAY)  
ISSUED AT 1114 PM EDT WED MAY 28 2025  
 
KEY MESSAGES:  
 
1. RAINY PATTERN CONTINUES.  
 
DISCUSSION:  
 
THE RAINY PATTERN CONTINUES IN THE SHORT TERM. ANOTHER WAVE OF  
SHOWERS WILL BEGIN TO LIFT NORTH ACROSS THE FORECAST AREA AROUND  
AND SHORTLY AFTER DAYBREAK, WITH RAIN CHANCES CONTINUING THROUGH  
MID AFTERNOON BEFORE DIURNAL TRENDS TAKE OVER AND RAIN TAPERS OFF.  
EXPECTING MOSTLY SHOWERS WITH THIS BUT SOME THUNDERSTORMS COULD BE  
EMBEDDED. THEN FRIDAY MORNING A SHORTWAVE ALOFT WILL PUSH A COLD  
FRONT THROUGH THE REGION DURING THE MORNING TO MIDDAY TIME FRAME,  
WITH WIDESPREAD SHOWERS AND THUNDERSTORMS ACCOMPANYING THE FRONT.  
SEVERE CHANCES SEEM QUITE LOW AS INSTABILITY IS NEGLIGIBLE AND  
SHEAR NOT EXCEPTIONALLY STRONG.  
 

 
   
LONG TERM
 
 
(FRIDAY NIGHT THROUGH NEXT THURSDAY)  
ISSUED AT 1114 PM EDT WED MAY 28 2025  
 
KEY MESSAGES:  
 
1. LARGE TROUGH OVER THE EASTERN CONUS FRIDAY NIGHT THROUGH THE  
WEEKEND WILL KEEP TEMPERATURES AROUND/BELOW NORMAL.  
 
2. PATTERN SHIFT BEGINS SUNDAY NIGHT INTO MONDAY FOR NOTABLE  
WARMUP AND DRIER CONDITIONS THROUGH MIDWEEK.  
 
3. POSSIBLE RETURN OF RAIN FOR LATTER HALF OF THE WEEK.  
 
DISCUSSION:  
 
BEHIND THE FRONT FRIDAY A LARGE UPPER TROUGH CARVES OUT A HOME  
OVER THE EASTERN CONUS, IN PARTICULAR THE GREAT LAKES AND  
NORTHEAST. JET ENERGY ALOFT WILL LEAD TO SOME SPOTTY SHOWERS  
ACROSS THE CWA BOTH SAT AND SUN AFTERNOONS, BUT EXPECT COVERAGE  
AND AMOUNTS TO BE LIGHT.  
 
SUNDAY NIGHT INTO MONDAY THE UPPER TROUGH MOVES EAST AND HIGH  
PRESSURE BUILDS OVERHEAD. THIS PERSISTS THROUGH AT LEAST TUESDAY  
AND POSSIBLY INTO WEDNESDAY, WITH TEMPERATURES WARMING BACK UP TO  
AROUND OR EVEN SLIGHTLY ABOVE NORMAL VALUES. LIKELY SEE DRY  
CONDITIONS MOST EVERYWHERE THOSE DAYS, WITH A SUMMER LIKE DIURNAL  
TREND OF AFTERNOON CONVECTION OVER THE MOUNTAINS POSSIBLE.  
 
ON WEDNESDAY THE RIDGE BEGINS TO BREAK DOWN. IT STILL LOOKS DRY  
THAT DAY, BUT IT APPEARS A RETURN OF LARGELY ZONAL FLOW IS  
PROBABLE BY THE END OF THE WEEK. THAT COULD PUT US BACK INTO AN  
ACTIVE PATTERN WITH THE POTENTIAL FOR MORE RAINFALL.  
 

 
   
AVIATION
 
 
(12Z TAFS)  
ISSUED AT 700 AM EDT THU MAY 29 2025  
 
SHOWERS AND EVENTUALLY THUNDERSTORMS WILL MOVE THROUGH THE REGION  
FOR MUCH OF THE DAYLIGHT HOURS. OUTSIDE OF ANY STORMS CEILINGS  
WILL REMAIN LOW FOR MUCH OF THE DAY. ANY LOCATIONS THAT DO RECEIVE  
MODERATE RAINFALL ARE EXPECTED TO EXPERIENCE A ROUND OF FOG  
OVERNIGHT AT THE TAIL END OF THIS TAF CYCLE.  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
CHATTANOOGA AIRPORT, TN 77 64 76 57 / 60 60 90 10  
KNOXVILLE MCGHEE TYSON AIRPORT, TN 77 62 72 55 / 50 60 100 20  
OAK RIDGE, TN 76 62 72 54 / 60 60 90 10  
TRI CITIES AIRPORT, TN 77 60 70 53 / 50 50 100 30  
 

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

 
 

 
 
SHORT TERM...DH  
LONG TERM....DH  
AVIATION...DH  
 
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