622  
FXUS64 KHUN 162316  
AFDHUN  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE HUNTSVILLE AL  
616 PM CDT SUN AUG 16 2026  
   
..NEW AVIATION
 
 
   
KEY MESSAGES
 
 
UPDATED AT 1045 AM CDT SUN AUG 16 2026  
 
- DANGEROUS HEAT WILL IMPACT THE TENNESSEE VALLEY THROUGH THE  
MIDDLE OF THIS WEEK, WITH MAJOR (LEVEL 3/4) TO EXTREME (LEVEL  
4/4) HEAT IMPACTS FORECAST.  
 
- A HEAT ADVISORY IS IN EFFECT FOR ALL OF NORTHERN ALABAMA AND  
SOUTHERN MIDDLE TENNESSEE THROUGH 7 PM MONDAY, WITH EXTENSIONS  
ON THE TABLE IN FUTURE UPDATES THROUGH POTENTIALLY MID-WEEK.  
 
- A SLIGHT (2 OUT OF 5) RISK FOR SEVERE THUNDERSTORMS IS FORECAST  
MONDAY ACROSS EASTERN FRANKLIN COUNTY TENNESSEE AND PORTIONS  
OF FAR NORTHEAST ALABAMA, WITH A MARGINAL (1 OUT OF 5) RISK  
THROUGH MOST OF THE AREA.  
 

 
   
NEAR TERM
 
 
(TONIGHT)  
ISSUED AT 330 PM CDT SUN AUG 16 2026  
 
THE FORECAST REMAINS ON TRACK WITH MINOR ADJUSTMENTS MADE TO POPS  
ALONG AND SOUTH OF THE TN RIVER DUE TO SOME POP UP SHOWERS THIS  
AFTERNOON. HAVE ADDED A LOW CHANCE (15% OR LESS) OF SHOWERS  
THROUGH THE NEXT COUPLE HOURS. OTHERWISE, LOW TEMPERATURES ARE  
STILL ON TRACK TO DROP INTO THE MID TO UPPER 70S. RELATIVELY DRY  
DEW POINT DEPRESSIONS SHOULD PREVENT WIDESPREAD FOG FORMATION  
AGAIN TONIGHT.  
 
PREVIOUS DISCUSSION:  
THE PRIMARY CONCERN CONTINUES TO BE HEAT AS  
AN UPPER LEVEL RIDGE PROCRASTINATES MOVING EASTWARD AND WE REMAIN  
IN A FAVORABLE AREA FOR ABOVE NORMAL TEMPERATURES. THIS  
AFTERNOON'S HIGHS ARE FORECAST TO WARM INTO THE MID TO UPPER 90S  
WITH HEAT INDICES UP TO 102-109 DEGREES. TONIGHT, LOWS ARE  
FORECAST TO DROP INTO THE MID TO UPPER 70S, WHICH WILL NOT PROVIDE  
MUCH RELIEF. A HEAT ADVISORY CONTINUES THROUGH 7 PM MONDAY. BE  
SURE TO STAY HYDRATED AND SEEK SHADE WHEN OUTDOORS TO AVOID HEAT-  
RELATED ILLNESS.  
 

 
   
SHORT TERM
 
 
(MONDAY THROUGH WEDNESDAY)  
ISSUED AT 1045 AM CDT SUN AUG 16 2026  
 
AN AREA OF LOW PRESSURE PUSHING EASTWARD THROUGH THE GREAT LAKES  
REGION IS FORECAST TO BRING AN ASSOCIATED COLD FRONT SOUTHEASTWARD  
INTO THE TENNESSEE VALLEY AND APPALACHIAN REGION MONDAY NIGHT.  
AHEAD OF THIS, BOTH HEAT AND SEVERE STORMS WILL BE ON THE TABLE AS  
HAZARDS MONDAY AFTERNOON INTO THE EVENING HOURS. ADDRESSING THE  
HEAT, HIGHS ARE FORECAST TO REACH THE MID TO UPPER 90S YET AGAIN  
ALONG WITH HEAT INDICES NEARING 110. THE RECENT HREF RUN HAS VERY  
LOW CHANCES (LESS THAN 5%) OF OUR AREA MEETING OR EXCEEDING 110  
DEGREE HEAT INDICES MONDAY AFTERNOON, WITH THE MOST LIKELY RANGE  
BEING AROUND 105-108 DEGREES. THUNDERSTORM DEVELOPMENT AND  
COEXISTING CLOUD COVER AHEAD OF THE COLD FRONT WILL BE THE FACTOR  
TO WATCH. IF THE FRONT SLOWS DOWN AND THE THUNDERSTORMS ARE  
DELAYED, THERE IS A LOW CHANCE WE COULD REACH EXTREME HEAT WARNING  
IN SOME LOCATIONS (ESPECIALLY URBAN HEAT ISLAND SPOTS SUCH AS  
HUNTSVILLE). WE HAVE OPTED TO HOLD OFF ON UPGRADING FOR NOW, BUT  
DO NOT RULE IT OUT IN FUTURE UPDATES AS THE FORECAST EVOLVES.  
 
SEVERE WEATHER-WISE, THE STORM PREDICTION CENTER HAS INCLUDED MOST  
OF THE AREA IN A MARGINAL RISK (LEVEL 1 OF 5) AND CLIPPED PORTIONS  
OF NORTHEASTERN AL AND SOUTHERN MIDDLE TN IN A SLIGHT RISK (LEVEL  
2 OF 5). THE PRIMARY CONCERN WITH ANY STORMS THAT ARE REALIZED  
WILL BE DAMAGING WINDS UP TO 60 MPH IN ADDITION TO HEAVY RAINFALL  
AND LIGHTNING. MODEL SOUNDINGS CONTINUE TO PORTRAY STEEP LOW LEVEL  
LAPSE RATES (9+ C/KM) COMBINED WITH DCAPE VALUES OVER 1100 J/KG AS  
WELL AS MLCAPE OVER 1400 J/KG. THESE FACTORS, COMBINED WITH THE  
TYPICAL INVERTED V SOUNDING PROFILE, WILL ATTRIBUTE TO AN  
INCREASED RISK OF DOWNBURSTS THROUGH THE AFTERNOON INTO THE  
EARLY EVENING HOURS. PWAT VALUES ARE IN THE RANGE OF 1.7-1.9",  
WHICH IS NEAR 90TH PERCENTILE PER BMX SOUNDING CLIMATOLOGY.  
COMBINED WITH THE FORECAST SLOW STORM MOVEMENT (LESS THAN 10 KTS),  
HEAVY RAINFALL WILL BRING A LOW CHANCE OF FLASH FLOODING WHICH  
WILL PRIMARILY BE IN AREAS OF POOR DRAINAGE. HEAVY DOWNPOURS WILL  
CAUSE TEMPORARY PONDING OF WATER ON ROADWAYS, WHICH WILL CREATE  
HAZARDOUS DRIVING CONDITIONS DURING AND SHORTLY AFTER ANY  
RAINFALL. SHEAR CONTINUES TO LOOK LESS THAN IMPRESSIVE WITH A LACK  
OF LOW LEVEL VORTICITY AND THEREFORE NOT ANTICIPATING TORNADOES  
TO BE A THREAT. BE SURE TO STAY WEATHER AWARE MONDAY AND HAVE  
MULTIPLE WAYS TO RECEIVE WARNING INFORMATION THROUGHOUT THE  
AFTERNOON.  
 
TUESDAY THROUGH WEDNESDAY, HEAT REMAINS A HAZARD WITH HIGHS  
FORECAST TO REACH THE 90S BOTH DAYS ALONG WITH HEAT INDICES UP TO  
105 DEGREES. A LOW CHANCE OF AN EXTENSION OF THE CURRENT HEAT  
ADVISORY (VALID THROUGH 7 PM MONDAY) EXISTS IF TEMPERATURES  
CONTINUE TO TREND HIGHER. OTHERWISE, DRY CONDITIONS ARE FORECAST  
THROUGH BOTH DAYS AFTER THE COLD FRONT SHIFTS SOUTH OF THE AREA.  
 

 
   
LONG TERM
 
 
(TUESDAY NIGHT THROUGH SATURDAY)  
ISSUED AT 1042 PM CDT SAT AUG 15 2026  
 
THE WEATHER LOOKS DRY ON WEDNESDAY, AS NW FLOW CONTINUES AND  
OTHERWISE CONDITIONS LOOK SIMILAR TO TEMPERATURES AND HEAT INDEX  
VALUES EXPECTED THE PREVIOUS DAY.  
 
EVEN COOLER TEMPERATURES ARE EXPECTED TOWARDS THE END OF NEXT  
WEEK, AS ANOTHER STRONGER FRONT MOVES SOUTHEAST INTO THE AREA AND  
STALLS. SHOWER AND THUNDERSTORM CHANCES MAY INCREASE MORE AS WE  
GET CLOSER TO THIS PERIOD. HIGHS IN THE UPPER 80S TO LOWER 90S ARE  
EXPECTED WITH THE INCREASING CLOUD COVER AND PRECIPITATION  
CHANCES.  
 

 
   
AVIATION
 
 
(00Z TAFS)  
ISSUED AT 616 PM CDT SUN AUG 16 2026  
 
VFR CONDITIONS WILL PREVAIL AT EACH TERMINAL THROUGH MUCH OF THE  
PERIOD. HOWEVER, SHRA/TSRA WILL DEVELOP ALONG A FRONT MONDAY  
AFTERNOON WHICH COULD RESULT IN LOCALIZED MVFR CONDITIONS DUE TO  
REDUCED VISIBILITIES/CEILINGS. HAVE HANDLED THIS WITH A PROB30  
FOR NOW BETWEEN 19-00Z. AWWS AND AMENDMENTS MAY BE NEEDED DURING  
THIS TIMEFRAME.  
 

 
   
HUN WATCHES/WARNINGS/ADVISORIES
 
 
AL...HEAT ADVISORY UNTIL 7 PM CDT MONDAY FOR ALZ001>010-016.  
 
TN...HEAT ADVISORY UNTIL 7 PM CDT MONDAY FOR TNZ076-096-097.  
 

 
 

 
 
NEAR TERM...HC  
SHORT TERM....HC  
LONG TERM....KTW  
AVIATION...AMP.24  
 
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