205  
FXUS64 KMRX 182329  
AFDMRX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MORRISTOWN TN  
729 PM EDT FRI APR 18 2025  
   
..NEW AVIATION
 
 
   
SHORT TERM
 
 
(THIS EVENING THROUGH SATURDAY)  
ISSUED AT 240 PM EDT FRI APR 18 2025  
 
KEY MESSAGE:  
 
1. UNSEASONABLY WARM TEMPERATURES ARE EXPECTED WITH BREEZY  
SOUTHWESTERLY WINDS DURING THE DAY.  
 
THIS EVENING/TONIGHT  
 
CURRENTLY THIS AFTERNOON, A BROAD RIDGE IS CENTERED ACROSS THE  
EASTERN U.S. WITH TROUGHING AND THE UPPER JET WELL TO OUR NORTHWEST.  
AT THE SURFACE, A WEAK LOW IS MOVING INTO THE GREAT LAKES REGION  
WITH BERMUDA HIGH PRESSURE IN THE ATLANTIC. THIS PATTERN HAS  
RESULTED IN CONTINUED WARMING AND BROAD SOUTHWESTERLY WINDS.  
EFFICIENT MIXING WILL CONTINUE ELEVATED FIRE WEATHER CONCERNS INTO  
THE EARLY EVENING BEFORE SUNSET. OTHERWISE, WARM AND DRY CONDITIONS  
WILL CONTINUE OVERNIGHT WITH BREEZY WINDS REMAINING OVER THE HIGHER  
ELEVATIONS.  
 
SATURDAY  
 
ON SATURDAY, TROUGHING TO THE NORTHWEST WILL SLOWLY ADVANCE  
EASTWARD. LOCALLY, THE 500MB RIDGE WILL INCREASE TO AN IMPRESSIVE  
5,920M WITH HEIGHTS OVER OUR AREA REACHING TO 5,880M. THESE VALUES  
ARE TYPICAL IN JUNE OR JULY, WHICH UNDERSCORES THE EXTENT OF HEATING  
EXPECTED. THIS WILL ALSO BE COMBINED WITH CONTINUED SOUTHWESTERLY  
FLOW AND BERMUDA HIGH PRESSURE TO OUR EAST. THE DAY WILL BE BREEZY  
BUT LIKELY NOT AS DRY AS TODAY. RECORD HIGH TEMPERATURES FOR THE DAY  
ARE 90 OR HIGHER, AND WE MAY NOT REACH QUITE THAT HIGH.  
 

 
   
LONG TERM
 
 
(SATURDAY NIGHT THROUGH NEXT FRIDAY)  
ISSUED AT 240 PM EDT FRI APR 18 2025  
 
KEY MESSAGES:  
 
1. DRY AND VERY WARM THIS WEEKEND. NEAR RECORD HIGH TEMPERATURES.  
 
2. WEAKENING FRONT BRINGS SHOWERS/STORMS MONDAY INTO MONDAY NIGHT.  
OVERALL SEVERE RISK IS LOW BECAUSE OF LIMITED INSTABILITY.  
 
3. IT WILL REMAIN WARM FOR THE REMAINDER OF THE PERIOD, WITH A  
SHOWER OR STORM POSSIBLE AT TIMES AS THE STATIONARY FRONT REMAINS  
NEAR THE AREA AND LIFTS BACK NORTH.  
 
DISCUSSION:  
 
AN ANOMALOUSLY STRONG 500MB RIDGE WITH 591-593 DAM HEIGHTS WILL  
RESULT IN WARM CONDITIONS ACROSS THE SOUTHEAST CONUS THIS WEEKEND  
WITH TEMPERATURES 10 TO 15 DEGREES ABOVE NORMAL ACROSS OUR FORECAST  
AREA. AFTERNOON HIGHS WILL BE NEAR RECORDS, ESPECIALLY ON SUNDAY.  
 
DAILY RECORD HIGH MAXIMUM TEMPERATURES  
 
DATE CHATTANOOGA KNOXVILLE TRI-CITIES OAK RIDGE  
04-19 91(2002) 90(1941) 90(1941) 90(2002)  
04-20 89(2002) 87(2002) 85(2023) 88(2002)  
 
A STRONG UPPER-LEVEL SHORTWAVE WILL FLATTEN THE UPPER-LEVEL RIDGE  
ACROSS THE REGION AND BRING A COLD FRONT WEST TO EAST ACROSS THE  
TENNESSEE VALLEY AND SOUTHERN APPALACHIANS ON MONDAY. WITH LIMITED  
HEIGHT FALLS, MID-LEVEL LAPSE RATES ARE WEAK RESULTING IN LIMITED  
INSTABILITY. THIS WILL MITIGATE MUCH OF A SEVERE WEATHER RISK;  
HOWEVER, ANY THUNDERSTORMS THAT DO OCCUR MAY PRODUCE GUSTY WINDS  
WITH GRADIENT WINDS AROUND 5K FT AGL OF AROUND 40 KT.  
 
THIS FRONT WILL STRUGGLE TO CLEAR THE AREA MONDAY NIGHT AND TUESDAY,  
AND WILL LIKELY STALL NEAR THE SOUTHERN PARTS OF THE FORECAST AREA.  
THIS SHOULD RESULT IN DRIER CONDITIONS ON TUESDAY ACROSS MOST OF THE  
AREA, ESPECIALLY NORTHERN COUNTIES NEAR KENTUCKY AND INTO VIRGINIA.  
BY TUESDAY NIGHT, THIS FRONT WILL START TO DRIFT BACK NORTH AS A  
WARM FRONT AND SOUTHWESTERLY FLOW BEGINS TO INCREASE ONCE AGAIN  
AHEAD OF A SHORTWAVE ACROSS THE SOUTHERN PLAINS.  
 
WE WILL BECOME WARM SECTORED ONCE AGAIN BY LATE NEXT WEEK. WITH LESS  
INFLUENCE FROM RIDGING EXPECTED ACROSS THE AREA, INSTABILITY APPEARS  
TO BE MORE FAVORABLE FOR DIURNAL CONVECTIVE DEVELOPMENT, ESPECIALLY  
ACROSS THE HIGHER ELEVATIONS EACH AFTERNOON OR ANY SUBTLE  
MCV/SHORTWAVE FEATURES THAT MAY LOCALLY ENHANCE CONVECTIVE COVERAGE.  
 

 
   
AVIATION
 
 
(00Z TAFS)  
ISSUED AT 725 PM EDT FRI APR 18 2025  
 
WINDS ARE TRENDING LIGHT AS THE SUN SETS AND PEAK AFTERNOON  
MIXING SUBSIDES. SOUTHWESTERLY H85 JET WILL BE STRONGEST TO OUR  
NORTHWEST OVERNIGHT, HOWEVER, NEAR 30-35KT FLOW COULD LEAD TO SOME  
PERIODS OF LLWS ACROSS THE AREA TONIGHT. SOUTHWEST WINDS AROUND  
10KTS WITH LOCALLY HIGHER GUSTS WILL RETURN TOMORROW AFTERNOON.  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
CHATTANOOGA AIRPORT, TN 60 88 63 86 / 0 0 0 0  
KNOXVILLE MCGHEE TYSON AIRPORT, TN 62 86 62 86 / 0 0 0 10  
OAK RIDGE, TN 60 85 61 86 / 0 0 0 10  
TRI CITIES AIRPORT, TN 55 83 58 84 / 0 0 0 10  
 

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

 
 

 
 
SHORT TERM...BW  
LONG TERM....JB  
AVIATION...KRS  
 
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