641  
FXUS64 KHUN 170550  
AFDHUN  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE HUNTSVILLE AL  
1250 AM CDT FRI JUL 17 2026  
   
..NEW AVIATION  
 
   
KEY MESSAGES  
 
UPDATED AT 918 PM CDT THU JUL 16 2026  
 
- EXPECT LOW TO MEDIUM CHANCES OF SHOWERS AND THUNDERSTORMS ON  
FRIDAY, WITH MEDIUM TO HIGH CHANCES OF SHOWERS AND STORMS  
SATURDAY AND SUNDAY.  
 
- NEAR SEASONABLE TEMPERATURES ARE FORECAST FOR THE UPCOMING  
WEEKEND.  
 
- MODERATE HEATRISK (LEVEL 2 OF 4) ARE FORECAST FRIDAY AND THIS  
WEEKEND, WITH HEAT INDEX VALUES PEAKING IN THE UPPER 90S TO 105  
DEGREES. MAJOR (LEVEL 3 OF 4) HEATRISK ARE FORECAST NEXT  
TUESDAY.  
 
 
   
NEAR TERM  
 
(REST OF TONIGHT AND FRIDAY)  
ISSUED AT 918 PM CDT THU JUL 16 2026  
 
IN A LARGER VIEW, UPPER LEVEL TROUGHING WAS PRESENT ACROSS THE  
PACIFIC NW, WITH BROAD UPPER RIDGING ACROSS MOST OF THE CONUS. A  
ZONAL WEST-EAST POLAR FLOW WAS MOVING OVER THE UNITED STATES AND  
CANADA BORDER. THIS FLOW AS IT WAS ORIENTED IN A SLIGHT ESE MANNER  
ACROSS THE MID ATLANTIC, WAS HELPING TO KEEP SMOKE FROM CANADIAN  
FIRES WELL NORTH OF THIS AREA.  
 
LOCALLY, AVAILABLE MOISTURE AND RESULTANT INSTABILITY FROM EARLIER  
DAYTIME HEATING HAS RESULTED IN ISOLATED SHOWERS ACROSS PORTIONS  
OF THE TENNESSEE VALLEY. SHOWER AND THUNDERSTORM ACTIVITY WAS A  
BIT MORE PLENTIFUL TO OUR NORTH AND EAST, WITH SLIGHTLY HIGHER  
AMOUNTS OF PRECIPITABLE WATER AND MORE BOUNDARY INTERACTION. WITH  
AN EXCEPTION OF ISOLATED SHOWERS SW OF MUSCLE SHOALS, OTHER  
ACTIVITY FOR THE MOST PART HAS DISSIPATED. 9 PM TEMPERATURES WERE  
FALLING THROUGH THE UPPER 70S/LOWER 80S, AFTER EARLIER HIGHS WERE  
AROUND 90. AS WE GO INTO THE LATTER HALF OF JULY WITH SLIGHTLY  
LONGER NIGHTS, WE CANNOT RULE OUT PREDAWN PATCHY FOG DEVELOPMENT  
MAINLY IN AND NEAR THOSE MORE FAVORED AREAS.  
 
WITH HIGH PRESSURE AT THE SURFACE AND ALOFT OVER THE AREA, EXPECT  
SIMILAR CONDITIONS TO CLOSE OUT THE WORK WEEK FRIDAY. EXPECT  
ANOTHER VERY WARM TO HOT DAY, WITH HIGHS RISING INTO THE UPPER 80S  
TO LOWER 90S, WITH HEAT INDEX VALUES FROM THE UPPER 90S TO 103.  
THE STRONG DAYTIME HEATING OF A SLIGHTLY MORE HUMID AIRMASS WILL  
RESULT IN SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS FORMING  
IN THE AFTERNOON TO EARLY EVENING. CONVECTION SHOULD REMAIN  
"GENERAL" IN INTENSITY, WITH THE USUAL STRONG GUSTY OUTFLOW WINDS,  
FREQUENT LIGHTNING, AND HEAVY DOWNPOURS.  
 
 
   
SHORT TERM  
 
(FRIDAY NIGHT THROUGH SUNDAY)  
ISSUED AT 918 PM CDT THU JUL 16 2026  
 
SHOWER ACTIVITY SHOULD DIMINISH IN COVERAGE AND INTENSITY FRI  
EVENING WITH THE LOSS OF DAYTIME HEATING. LOW TEMPERATURES BY  
DAYBREAK SAT SHOULD COOL ONLY INTO THE LOWER 70S. ANOTHER REPEAT  
PERFORMANCE LATER FOR BOTH DAYS SAT AND SUN, AS DAYTIME HEATING  
AND RESULTANT HIGHER INSTABILITY BRING MORE AFTERNOON TO EARLY  
EVENING SHOWER AND THUNDERSTORM DEVELOPMENT. SIMILAR STORM  
INTENSITY WITH GUSTY WINDS, FREQUENT LIGHTNING, AND HEAVY  
DOWNPOURS. HIGH TEMPERATURES BOTH DAYS SHOULD RISE TO AROUND 90,  
WITH HEAT INDEXES FROM THE UPPER 90S TO 105 (VERY SPOTTY COVERAGE  
OF THE HOTTEST VALUES). DEPENDING UPON TRENDS, HEAT ADVISORY  
CRITERIA COULD BE MET OVER THE WEEKEND SHOULD HIGH TEMPERATURES  
RISE A BIT MORE AND/OR COVER A LARGER AREA. THIS WILL BE EVALUATED  
IN FUTURE FORECASTS.  
 
 
   
LONG TERM  
 
(SUNDAY NIGHT THROUGH THURSDAY)  
ISSUED AT 918 PM CDT THU JUL 16 2026  
 
ON MONDAY, A DEEP LAYER NARROW TROUGH AXIS WILL BE LOCATED ACROSS  
THE EASTERN GULF OF AMERICA AS A STRONG UPPER TROUGH BEGINS TO  
DIG SOUTHEAST THROUGH THE EASTERN GREAT LAKES AND A STRONG  
ANTICYCLONE BUILDS ACROSS THE SOUTH CENTRAL U.S. THE RIDGE BUILDS  
EAST INTO THE SOUTHEAST U.S. TUESDAY BEFORE THE STRONG UPPER  
TROUGH SWINGS A COOL FRONT SOUTHEAST THROUGH THE MID ATLANTIC INTO  
THE TN VALLEY ON WEDNESDAY. SHOWER AND THUNDERSTORM CHANCES WILL  
REMAIN 20% OR LESS DURING THIS PERIOD WITH THE RIDGE IN PLACE, AND  
DESPITE A FRONTAL PASSAGE. TEMPERATURES WILL WARM INTO THE 90-95F  
RANGE MONDAY AND TUESDAY, THEN DROP INTO THE UPPER 80S TO LOWER  
90S ON WEDNESDAY, AND MIDDLE 80S TO AROUND 90 ON THURSDAY. THE  
HEAT RISK LEVEL WILL REACH MAJOR (3 OUT OF 4) ON TUESDAY WHEN HEAT  
INDEX VALUES REACH 100-105F FOR MOST AREAS AND WBGTS REACH THE  
MIDDLE TO UPPER 80S.  
 
 
   
AVIATION  
 
(06Z TAFS)  
ISSUED AT 1250 AM CDT FRI JUL 17 2026  
 
VFR CONDITIONS ARE FORECAST TO PERSIST THROUGH MUCH OF THE  
OVERNIGHT HOURS HOWEVER THERE IS A LOW CHANCE FOG COULD DEVELOP IF  
CLOUD COVER STAYS MINIMAL. WINDS SHOULD REMAIN NEAR CALM INTO THE  
MORNING HOURS WITH INCREASING CHANCES FOR SHOWERS AND  
THUNDERSTORMS TOWARD THE AFTERNOON, ESPECIALLY NEAR KHSV.  
REDUCTIONS TO MVFR OR LOWER CATEGORIES WILL BE LIKELY DURING  
THUNDERSTORMS, OTHERWISE VFR CONDITIONS ARE FORECAST TO PERSIST.  
 
 
   
HUN WATCHES/WARNINGS/ADVISORIES  
 
AL...NONE.  
TN...NONE.  
 
 
 
 
NEAR TERM...RSB  
SHORT TERM....RSB  
LONG TERM....17  
AVIATION...25  
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