017  
FXUS64 KMRX 251901  
AFDMRX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MORRISTOWN TN  
301 PM EDT SAT JUL 25 2026  
   
..NEW DISCUSSION
 
 
   
KEY MESSAGES
 
 
UPDATED AT 253 PM EDT SAT JUL 25 2026  
 
- SCATTERED SHOWERS AND STORMS ARE EXPECTED TONIGHT. IF MULTIPLE  
STORMS TRACK OVER ONE LOCATION, ISOLATED FLOODING WILL BE  
POSSIBLE.  
 
- A WARMING TREND BEGINS TOMORROW INTO THE NEW WORK WEEK. MONDAY  
AND TUESDAY WILL BE THE HOTTEST DAYS AS HEAT INDICES IN THE MID  
90S TO LOW 100S BECOME MORE COMMONPLACE, ESPECIALLY IN THE  
CENTRAL AND SOUTHERN VALLEY.  
 
- ADDITIONAL PERIODS OF ISOLATED TO SCATTERED SHOWERS AND STORMS  
ARE POSSIBLE MONDAY AND TUESDAY. AT THIS TIME, TUESDAY AFTERNOON  
AND EVENING HOLDS THE GREATEST POTENTIAL TO HAVE A FEW STRONG  
TO SEVERE STORMS WITH GUSTY WINDS THE PRIMARY HAZARD.  
 
- MOSTLY DRY CONDITIONS WITH SLIGHT IMPROVEMENTS TO THE HEAT AND  
HUMIDITY ARE EXPECTED MID TO LATE WEEK.  
 

 
   
DISCUSSION
 
 
ISSUED AT 253 PM EDT SAT JUL 25 2026  
 
A RIDGE AXIS REMAINS CENTERED WELL TO OUR WEST WHILE BOUTS OF ENERGY  
WILL ROTATE THROUGH MEAN FLOW ALOFT THIS AFTERNOON AND TONIGHT. THIS  
WILL AMPLIFY TROUGHING OVER THE MID-ATLANTIC INTO THE SOUTHERN  
APPALACHIANS. H85 AND HIGHER ALTITUDE FLOW WILL SEE MINOR  
ENHANCEMENTS IN RESPONSE TO THE INCREASING VORTICITY ADVECTION  
TONIGHT. BECAUSE OF THIS, THE HREF SUITE DEPICTS DEVELOPING  
SCATTERED SHOWERS AND STORMS ACROSS THE REGION.  
 
THERE WILL BE A LOW RISK OF ISOLATED FLOODING THROUGH THE NIGHT.  
ASPECTS OF THE ATMOSPHERE IN FAVOR OF ISOLATED FLOODING WILL BE HIGH  
FREEZING-LEVELS, ANOMALOUS PWATS, SKINNY CAPE PROFILES, AND A FEW  
LOCATIONS THAT REMAIN WITH POOR ANTECEDENT SOIL CONDITIONS. WORKING  
AGAINST THE THREAT OF ISOLATED FLOODING IS STORM MOTION AND LACK OF  
A SURFACE BOUNDARY TO TRAIN ALONG. ADDITIONALLY, LATEST RAP AND  
NAMBUFR SOUNDINGS BOTH DEPICT A RATHER DRY ATMOSPHERE AT ~550MB AND  
HIGHER, SUGGESTING LIMITED DEPTH OF SATURATION.  
 
SUNDAY AFTERNOON LOOKS TO BE MOSTLY DRY, THOUGH AN ISOLATED SHOWER  
OR STORM CANNOT BE TOTALLY RULED OUT. BY SUNDAY NIGHT INTO EARLY  
MONDAY MORNING CAMS ARE SUGGEST A MCS PROGRESSING THROUGH NORTHERN  
KY AND SOUTHWARD THROUGH PORTIONS OF CENTRAL AND EAST TENNESSEE.  
THIS ACTIVITY MOVES QUITE QUICK SO FLOODING SHOULD NOT BE OF  
CONCERN. THE MAIN FOCUS WILL BE KEEPING AN EYE ON THE POTENTIAL FOR  
SOME STRONG TO DAMAGING WIND GUSTS. NAM SOUNDINGS DEPICT A FAIRLY  
STOUT LOW-LEVEL INVERSION SO CONFIDENCE IS LOW THAT DAMAGING GUSTS  
COULD MAKE IT TO THE SURFACE. WILL HAVE TO KEEP AN EYE ON HOW THE  
POTENTIAL CAPE GRADIENT PLAYS OUT ALONGSIDE TIMING TRENDS.  
 
A MORE POTENT SHORTWAVE IS EXPECTED TO PROMOTE DEVELOPMENT OF AN  
UPPER LOW OVER THE EASTERN GREAT LAKES AND MID-ATLANTIC TUESDAY INTO  
WEDNESDAY. A SURFACE LOW DEVELOPS IN RESPONSE, AND AN ASSOCIATED  
COLD FRONT WILL BRING INCREASING CHANCES FOR SHOWERS AND STORMS.  
NAMBUFR SOUNDINGS HAVE QUITE AN IMPRESSIVE THERMODYNAMIC PROFILE AT  
LEAST FOR TUESDAY AFTERNOON, BUT TIMING OF THE STORMS MAY NOT  
NECESSARILY WORK OUT TO TAP INTO PEAK HEATING AND THE LATEST HI-  
RESOLUTION GUIDANCE DOES NOT QUITE MAKE IT INTO THOSE OVERNIGHT  
HOURS. LREF JOINT PROBABILITIES OF MUCAPE 1500+ J/KG AND SHEAR  
30+KTS ARE GENERALLY AROUND 40 TO 60% IN OUR NORTHEASTERN LOCATIONS  
WHERE A DAY 4 SLIGHT RISK IS CURRENTLY IN PLACE. PRIMARY HAZARD  
WOULD BE DAMAGING WINDS.  
 
REGARDING TEMPERATURES, SUNDAY THROUGH TUESDAY WILL LEAN HOT & HUMID.  
HEAT INDICES WILL BE GREATEST MONDAY AND TUESDAY, WITH NEAR TO LOW  
100 DEGREE VALUES EXPECTED TO CREEP INTO THE CENTRAL VALLEY. POST  
FROPA, MOSTLY DRY AND SLIGHTLY COOLER/LESS HUMID CONDITIONS ARE  
EXPECTED MID TO LATE WEEK.  
 

 
   
AVIATION
 
 
(18Z TAFS)  
ISSUED AT 132 PM EDT SAT JUL 25 2026  
 
VERY LIGHT SHOWERS ARE STILL TRAVERSING THE AREA, MAINTAINED SOME  
VCSH AT CHA AND TYS. TONIGHT LOW CONFIDENCE IN WEATHER, WITH  
DEGRADATION TO MVFR CIGS MEDIUM CONFIDENCE, AND SCATTERED SHOWERS  
AND THUNDERSTORMS POSSIBLY BETWEEN TYS AND TRI OVERNIGHT, THOUGH  
LOW CONFIDENCE IN LOCATION, COVERAGE, AND INTENSITY. APART FROM  
LIGHTNING, LOW CIGS AND LOW VIS DURING STORMS. POST 12Z CONDITIONS  
SHOULD BEGIN GRADUALLY IMPROVING, BUT MAY REMAIN MVFR FOR MUCH OF  
THE AREA INTO THE MORNING.  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
CHATTANOOGA AIRPORT, TN 73 91 72 93 / 60 20 20 30  
KNOXVILLE MCGHEE TYSON AIRPORT, TN 71 88 71 90 / 80 30 30 30  
OAK RIDGE, TN 70 88 70 90 / 80 20 20 30  
TRI CITIES AIRPORT, TN 66 84 66 86 / 60 50 20 20  
 

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

 
 

 
 
DISCUSSION...KRS  
AVIATION...WELLINGTON  
 
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