050  
FXUS64 KHUN 012232  
AFDHUN  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE HUNTSVILLE AL  
532 PM CDT SUN AUG 1 2021  
   
UPDATE
 
 
FOR 00Z TAFS.  
 

 
   
NEAR TERM
 
(TONIGHT)  
ISSUED AT 145 PM CDT SUN AUG 1 2021  
 
COMPLICATED SETUP THIS AFTERNOON WITH ONE PRIMARY DIFFERENTIAL  
HEATING BOUNDARY FROM EARLIER CONVECTION TODAY SETUP ACROSS CENTRAL  
ALABAMA. FURTHER NORTH, A WEAK FRONTAL BOUNDARY STILL WEAVES IT WAY  
SOMEWHERE FROM NORTH CENTRAL MISSISSIPPI INTO SOMEWHERE IN  
NORTHEASTERN ALABAMA AT THIS HOUR. SUNSHINE HAS BEEN ABLE TO SHOW  
ITSELF ACROSS MANY LOCATIONS, ESPECIALLY SOUTH OF THE TENNESSEE RIVER  
RIGHT NOW. THIS HAS ALLOWED TEMPERATURES TO CLIMB BACK INTO THE 80  
TO 83 DEGREE RANGE IN MOST LOCATIONS, WITH A FEW SPOTS IN NW ALABAMA  
CREEPING UP TO AROUND 85 DEGREES.  
 
A RE-ENFORCING COLD FRONT BEHIND ALL OF THIS HAS QUICKLY MADE ITS WAY  
SOUTH TODAY. THIS FRONT IS EXPECTED TO MERGE WITH THE ONE CURRENTLY  
OVER THE AREA AND SHIFT IT SOUTHWARD QUICKLY LATE THIS AFTERNOON  
INTO THE EVENING HOURS. UNFORTUNATELY, WITH THE SUNSHINE COMES SOME  
INCREASING INSTABILITY. CANNOT RULE OUT SOME ISOLATED TO SCATTERED  
THUNDERSTORMS DEVELOPING THIS AFTERNOON, BEFORE THE RE-ENFORCED  
FRONTAL BOUNDARY MOVES SOUTH OF THE AREA. GIVEN CURRENT TRENDS AND  
MODEL PARAMETERS, 1000 TO 2000 J/KG OF CAPE, 20 TO 35 KNOTS OF SHEAR,  
AND NOT BAD MID LEVEL LAPSE RATES AROUND 6 DEGREES CELSIUS/KM LOOK  
POSSIBLE BEFORE THE FRONT PUSHES THROUGH. SO CANNOT RULE OUT A STRONG  
THUNDERSTORM OR TWO. THE MAIN THREATS WITH THE STRONGEST STORMS  
WOULD BE WINDS GUSTS TO 50 MPH, FREQUENT LIGHTNING, AND LOCALLY HEAVY  
DOWNPOURS.  
 
DO EXPECT PRECIPITATION CHANCES TO END AND BE SOUTH OF THE AREA BY  
THE EVENING HOURS. SOME CLOUD COVER WILL LINGER TONIGHT THOUGH AT  
TIMES. THIS WILL LIKELY KEEP LOWS A TAD WARMER THAN THEY COULD BE  
WITH THE MUCH DRIER AIR THAT PUSHES SOUTH BEHIND THE FRONT OVERNIGHT.  
LOWS IN THE LOWER TO MID 60S LOOK REASONABLE.  
   
SHORT TERM
 
(MONDAY THROUGH TUESDAY)  
ISSUED AT 145 PM CDT SUN AUG 1 2021  
 
DURING THE DAY ON MONDAY, GUIDANCE KEEPS THE FRONT ACROSS EITHER THE  
NORTHERN GULF COAST STATES OR SOUTHERN ALABAMA. THEY ALSO DEVELOP A  
SURFACE LOW ON THE FRONT. THEY ALSO HINT AT A WEAK INVERTED TROUGH  
AXIS POSSIBLY EXTENDING NORTH FROM THIS LOW AS WELL. THIS COULD PUSH  
SOME VERY ISOLATED SHOWERS BACK INTO PORTIONS OF CULLMAN COUNTY  
DURING THE DAY. WITH INCREASING CLOUD COVER ASSOCIATED WITH THE INVERTED  
TROUGH AXIS, TEMPERATURES WILL LIKELY ONLY BE A FEW DEGREES WARMER  
ON MONDAY (WITH OVERALL MORE MORNING SUNSHINE EXPECTED). HIGHS SHOULD  
TOP OUT IN THE 83 TO 87 DEGREE RANGE IN MOST AREAS.  
 
MONDAY NIGHT INTO TUESDAY THE SURFACE HIGH OVER THE NORTHERN CONUS  
BUILDS A BIT MORE TO THE SOUTHEAST. COULD SEE A FEW ISOLATED SHOWERS  
OR THUNDERSTORMS IN FAR NORTHEASTERN ALABAMA IN THE AFTERNOON. HIGHS  
SHOULD AGAIN BE IN THE MID 80S. A DRIER AIRMASS AND GOOD RADIATIONAL  
COOLING CONDITIONS (CLEAR SKIES/LIGHT WINDS) WILL HELP TO PROVIDE  
MUCH COOLER OVERNIGHT TEMPERATURES ON TUESDAY NIGHT, AS LOWS DROP  
INTO THE 61 TO 65 DEGREE RANGE IN MOST AREAS.  
   
LONG TERM
 
(TUESDAY NIGHT THROUGH SATURDAY)  
ISSUED AT 145 PM CDT SUN AUG 1 2021  
 
AN UPPER-TROUGH WILL REMAIN THE DOMINANT WEATHER FEATURE ACROSS THE  
EASTERN CONUS FOR THE REMAINDER OF THE WORK WEEK. THE END RESULT WILL  
BE A PERIOD OF FAIRLY BENIGN WEATHER AND SLIGHTLY BELOW NORMAL  
TEMPERATURES WITH HIGHS IN THE MID TO UPPER 80S. IN FACT, A COUPLE  
OF "REINFORCING" SHORTWAVES WILL PASS THROUGH THE AREA WEDNESDAY AND  
AGAIN FRIDAY, KEEPING THE HEAT AT BAY TO OUR WEST. MOISTURE WILL BE  
QUITE LIMITED AHEAD OF THESE FEATURES, BUT STILL EXPECT THERE TO BE  
ENOUGH OF IT (COMBINED WITH SUFFICIENT LIFT AND INSTABILITY) TO  
GENERATE SOME SCATTERED SHOWERS AND THUNDERSTORMS DURING THIS PERIOD.  
A STRONGER UPPER-LEVEL RIDGE OVER THE PLAINS WILL BEGIN TO BUILD  
INTO THE AREA BY THE UPCOMING WEEKEND. THIS WILL RESULT IN A SLIGHTLY  
DRIER FORECAST AS WELL AS A GRADUAL WARMING TREND AS HIGHS RETURN TO  
SEASONABLE LEVELS FOR EARLY AUGUST IN THE LOWER 90S.  
 

 
   
AVIATION
 
(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)  
ISSUED AT 532 PM CDT SUN AUG 1 2021  
 
VFR FLIGHT WEATHER CONDITIONS ARE FORECAST. DRIER NORTH FLOW WILL  
ARRIVE BEHIND A COLD FRONT TONIGHT INTO MONDAY.  
 

 
   
HUN WATCHES/WARNINGS/ADVISORIES
 
 
AL...NONE.  
TN...NONE.  

 
 

 
 
NEAR TERM...KTW  
SHORT TERM...KTW  
LONG TERM...AMP.24  
AVIATION...17  
 
FOR MORE INFORMATION PLEASE VISIT OUR WEBSITE  
AT WEATHER.GOV/HUNTSVILLE.  
 
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