031  
FXUS64 KMRX 130541  
AFDMRX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MORRISTOWN TN  
141 AM EDT SUN JUL 13 2025  
   
..NEW SHORT TERM, LONG TERM  
 
   
SHORT TERM  
 
(TODAY AND TONIGHT)  
ISSUED AT 135 AM EDT SUN JUL 13 2025  
 
KEY MESSAGES:  
 
1. ADDITIONAL SHOWERS AND STORMS EXPECTED THIS AFTERNOON. OVERALL,  
LESSER COVERAGE AND CHANCES FOR AN ISOLATED SEVERE STORM RELATIVE TO  
YESTERDAY. STRONG GUSTY WINDS UP TO 40MPH AND ISOLATED FLASH  
FLOODING WILL BE THE MAIN CONCERNS WITH ANY STRONGER STORM.  
 
DISCUSSION:  
 
A PATTERN OF PERSISTENCE FOR THE OVERNIGHT HOURS. RIVER VALLEY FOG  
IS BEGINNING TO SHOW ON SATELLITE IMAGERY WHILE RIVER VALLEYS AND  
LOCATIONS THAT OBSERVED MODERATE TO HEAVY RAINFALL THIS AFTEROON  
WILL HAVE THE HIGHEST CHANCES TO SEE SOME PATCHY DENSE FOG. WITH  
SOME WEAK 500MB VORTICITY IN PLACE IT IS NOT OUT OF THE QUESTION TO  
SEE AN ISOLATED SHOWER OR RUMBLE OF THUNDER IN THE AM HOURS.  
HOWEVER, WITH NO HEATING TO COUNTERACT POOR SYNOPTIC FORCING, NO SIG  
WEATHER IS EXPECTED.  
 
FOR THIS AFTERNOON, UPPER TROUGH WILL REMAIN IN PLACE OVER THE  
WESTERN GREAT LAKES WITH AN 80-85KT H3 JET EXTENDING FROM NORTHERN  
ILLINOIS INTO EASTERN CANADA. THERE IS NO NOTABLE IMPULSE ROUNDING  
THE BASE OF THE TROUGH THIS AFTERNOON, AND RAP SOUNDINGS SHOW  
EFFECTIVE BULK SHEAR LESS THAN 10KTS AS A RESULT. ADDITIONAL  
ISOLATED TO SCATTERED SHOWERS AND STORMS ARE EXPECTED IN THE  
AFTERNOON AND EVENING BUT ORGANIZATION AND ANY SEVERE CHANCES SEEM  
UNLIKELY DUE TO THE LACK OF SHEAR. 1.7-1.8" PWS AND DCAPE BETWEEN  
600-900J/KG COULD STILL LEAD TO THE OCCASIONAL PRECIP LOADED  
DOWNBURST WITH WINDS TO 40MPH AND ISOLATED FLASH FLOODING IN THE  
EVENT ACTIVITY OCCURS OVER VULNERABLE SOILS.  
 
 
   
LONG TERM  
 
(MONDAY THROUGH SATURDAY)  
ISSUED AT 135 AM EDT SUN JUL 13 2025  
 
KEY MESSAGES:  
 
1. DAILY SUMMER-TIME CONVECTION CONTINUES. COVERAGE WILL BE MORE  
ISOLATED TO SCATTERED TO BEGIN THE PERIOD, WITH POTENTIAL FOR  
INCREASED COVERAGE AS TROUGHING INFLUENCE INCREASES THE LATTER HALF  
OF NEXT WEEK.  
 
2. HOT CONDITIONS RETURN AS AN UPPER RIDGE BUILDS BACK INTO THE  
REGION FOR THE MIDDLE PART OF THE WORK WEEK. HEAT INDICES IN THE MID  
90S TO LOW 100S WILL BECOME MORE COMMON ACROSS VALLEY LOCATIONS.  
 
DISCUSSION:  
 
UPPER TROUGH PIVOTS EASTWARD MONDAY WITH CONTINUED CHANCES FOR  
DIURNAL CONVECTION. LATEST NAMBUFR SOUNDINGS SUGGEST THAT EFFECTIVE  
SHEAR REMAINS 10KTS OR LESS, WITH TYPICAL SUMMER-TIME DIURNAL  
CONVECTION EXPECTED. A FEW STRONGER STORMS COULD LEAD TO WIND GUSTS  
UP TO 40MPH AND ISOLATED FLASH FLOODING. FOR NOW, THIS IS ULTIMATELY  
THE THREATS EXPECTED WITH CONVECTION EACH DAY THROUGH THE EXTENDED.  
MONDAY WILL BE HOT AND MUGGY WITH WITH HEAT INDICES NEAR 100F FOR  
MUCH OF THE SOUTHERN AND CENTRAL VALLEY. LOW TO MID 90S ARE MORE  
LIKELY FOR NORTHERN VALLEY INTO SOUTHWEST VIRGINIA.  
 
BY MID-WEEK THE RIDGE WILL CONTINUE TO BUILD ACROSS THE EASTERN  
CONUS. WHILE CHANCES FOR DIURNAL CONVECTION PERSISTS, THE MAIN FOCUS  
WILL BE ON HEAT INDICES NEAR THE LOW 100S BECOMING MORE COMMON,  
ESPECIALLY CENTRAL VALLEY AND FURTHER SOUTH. TUESDAY AND WEDNESDAY  
ARE CURRENTLY LOOKING TO BE THE WARMEST DAYS.  
 
BY THURSDAY A SHORTWAVE TROUGH WILL BE DIGGING INTO THE NORTHERN  
CONUS. WITH WEAKENING SUBSIDENCE ALOFT THERE IS POTENTIAL TO SEE  
INCREASED COVERAGE OF AFTERNOON SHOWER AND STORM ACTIVITY BUT  
TEMPERATURES WILL TREND CLOSER TO SEASONAL NORMAL. A HUMID AIR MASS  
WILL KEEP INDICES IN THE 90S TO NEAR 100. UPPER RIDGE LOOKS TO  
BECOME DOMINANT ONCE AGAIN NEXT WEEKEND, BUT WITH NO SUBSTANTIAL  
AREA OF SFC HIGH PRESSURE BUILDING INTO TO SUPPRESS CONVECTION,  
DAILY SHOWER AND STORM CHANCES REMAIN RELENTLESS.  
 
 
   
AVIATION  
 
(06Z TAFS)  
ISSUED AT 1140 PM EDT SAT JUL 12 2025  
 
FOG/LOW CIG DEVELOPMENT EARLY IN THE PERIOD LOOKS MOST LIKELY AT  
TRI WHERE THE MORE SIGNIFICANT PRECIPITATION OCCURRED LATE THIS  
AFTERNOON, AND WILL INCLUDE MVFR CIGS/VSBY THERE FOR NOW AND  
LOWER CONDITIONS WILL BE POSSIBLE. WILL SEE SCATTERED SHOWERS AND  
THUNDERSTORMS AROUND AGAIN, AND WILL INCLUDE PROB30 GROUPS ALL  
SITES AROUND TIME OF HIGHEST PROBABILITY. OUTSIDE OF ANY EARLY  
FOG/LOW CLOUDS (MAINLY TRI) AND POSSIBLE CONVECTION, VFR  
CONDITIONS ARE EXPECTED.  
 
 
   
PRELIMINARY POINT TEMPS/POPS  
 
CHATTANOOGA AIRPORT, TN 93 73 95 74 / 40 10 30 10  
KNOXVILLE MCGHEE TYSON AIRPORT, TN 92 72 94 73 / 40 20 40 20  
OAK RIDGE, TN 91 71 93 72 / 40 20 40 10  
TRI CITIES AIRPORT, TN 87 68 89 69 / 40 30 50 30  
 
 
   
MRX WATCHES/WARNINGS/ADVISORIES  
 
NC...NONE.  
TN...NONE.  
VA...NONE.  
 
 
 
 
SHORT TERM...KRS  
LONG TERM....KRS  
AVIATION...  
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