772  
FXUS64 KHUN 051951  
AFDHUN  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE HUNTSVILLE AL  
251 PM CDT WED AUG 5 2020  
   
NEAR TERM
 
(TONIGHT)  
ISSUED AT 251 PM CDT WED AUG 5 2020  
 
AS EXPECTED, MUCH OF THIS AFTERNOON'S THUNDERSTORM ACTIVITY IS  
FOCUSED ACROSS NE AL, CLOSER TO A VERY WEAK BOUNDARY MARKED BY A  
GRADIENT IN SURFACE DEW POINTS. CONVECTIVE ACTIVITY IS LIKELY BEING  
HAMPERED BY A PRONOUNCED DRY LAYER IN THE MID LEVELS (REFLECTED BY  
THE 7.3 AND 6.9UM CHANNELS). SATELLITE-DERIVED PRECIPITABLE WATER  
VALUES ARE IN THE 10TH TO 25TH PERCENTILES CLIMATOLOGICALLY (IN  
OTHER WORDS, IT'S DRIER THAN NORMAL ALOFT). WITH THE HUN CWFA ON THE  
DRIER SIDE OF THE BOUNDARY, SURFACE DEWPOINTS REMAIN GENERALLY IN THE  
MID 60S, MAKING FOR A PLEASANT BUT SEASONABLY WARM AFTERNOON.  
 
BASED ON CURRENT RADAR TRENDS, POPS HAVE BEEN REDUCED FOR THE REST OF  
THE AFTERNOON AND EARLY EVENING, AND SHOULD TAPER OFF QUICKLY WITH  
SUNSET. RAIN CHANCES OVERNIGHT ARE NOT ZERO BUT LOW ENOUGH TO AVOID  
MENTIONING AFTER ABOUT 04Z. AS WITH THIS MORNING, FOG IS A  
POSSIBILITY IN THE PROTECTED RIVER VALLEYS, AND THE FORECAST WILL  
CONTINUE TO REFLECT THIS. LOW TEMPERATURES WILL STAY CLOSE TO  
PERSISTENCE AND BLENDED GUIDANCE, GENERALLY IN THE MID 60S.  
   
SHORT TERM
 
(THURSDAY THROUGH FRIDAY)  
ISSUED AT 251 PM CDT WED AUG 5 2020  
 
THAT LOW-LEVEL BOUNDARY WILL REMAIN STATIONARY THURSDAY, AND SHOULD  
CONTINUE TO FOCUS SCATTERED SHOWERS/STORMS OVER NE AL AGAIN TOMORROW  
AFTERNOON. THE MID-LEVEL DRYING SEEN TODAY MAY MODERATE SOMEWHAT  
TOMORROW, BUT PWATS SHOULD STILL REMAIN BELOW NORMAL, AND THAT MAY  
STILL REDUCE PRECIP COVERAGE SLIGHTLY. THE IMPACT OF ALL THIS MEANS  
THAT TOMORROW SHOULD BE VERY SIMILAR TO TODAY, WITH HIGHS TOPPING OUT  
NEAR 90.  
 
SOME VERY MINOR MOISTURE RECOVERY IS POSSIBLE FRIDAY, BUT THE BAGGY MID-  
LEVEL TROUGH AXIS IN PLACE OVER THE AREA WILL FINALLY SLIDE EAST,  
PLACING THE AREA IN A RELATIVELY DRIER NW FLOW. MUCH OF THE MODEL/  
ENSEMBLE GUIDANCE KEEPS THE REGION COMPLETELY DRY FOR FRIDAY,  
ALTHOUGH A FEW ROGUE SHOWERS COULD CROP UP NEAR THE GEORGIA BORDER.  
WITH FEWER CLOUDS/SHOWERS, TEMPERATURES SHOULD REACH THE LOWER 90S  
MORE READILY, AND IT IS POSSIBLE THAT BLENDED GUIDANCE IS TOO LOW.  
   
LONG TERM
 
(FRIDAY NIGHT THROUGH TUESDAY)  
ISSUED AT 251 PM CDT WED AUG 5 2020  
 
THE WEAK UPPER LEVEL TROUGH POSITIONED TO OUR NORTHEAST WILL LIFT UP  
AND OUT OF THE EAST COAST AS WE APPROACH THE WEEKEND. A TROUGH  
BUILDING INTO THE PACIFIC NW WILL HELP PUSH A RIDGE INTO THE TN  
VALLEY, AND ITS INFLUENCE WILL LEAD TO DECREASING RAIN CHANCES AND  
INCREASING TEMPERATURES AS WE ROUND OUT THE WEEK. DIURNAL CONVECTION  
IS EXPECTED TO RETURN THIS WEEKEND, AND THANKS TO A SURGE OF  
MOISTURE ASSOCIATED WITH A LINGERING WARM FRONT, HEAT INDICES WILL  
ONCE AGAIN TREND TOWARDS 100 DEGREES. AS THE PACIFIC NW TROUGH  
PUSHES EASTWARD EARLY NEXT WEEK, WEAKNESSES BEGIN TO DEVELOP IN THE  
GOVERNING RIDGE. THIS COUPLED WITH THE PUSH OF THE STALLED FRONT  
NORTHWARD INTO THE TN VALLEY AND SHORTWAVE DISTURBANCES TRAVERSING  
THE RIDGE WILL LEAD TO INCREASED CHANCES FOR THE DEVELOPMENT OF  
SCATTERED SHOWERS AND THUNDERSTORMS. DESPITE THE LIKELIHOOD OF  
CONVECTIVE DEVELOPMENT, TEMPERATURES WILL REMAIN SEASONABLE IN THE  
LOWER 90S DURING THE DAY AND LOW 70S AT NIGHT.  
 

 
   
AVIATION
 
(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)  
ISSUED AT 1246 PM CDT WED AUG 5 2020  
 
VFR CONDITIONS ARE GENERALLY EXPECTED THRU 18Z/06. SCT-BKN VFR  
CUMULUS WILL BE THE RULE THIS AFTN. WIDELY SCATTERED SHRA OR EVEN A  
FEW TSRA CAN'T BE RULED OUT, MORESO AT KHSV THAN KMSL. CHANCES ARE  
TOO LOW AT THE TERMINALS TO MENTION BEYOND VCSH AT KHSV; CHANCES ARE  
HIGHER E OF KHSV. MAY SEE SOME PATCHY MVFR FOG AGAIN OVERNIGHT, BUT  
AS WITH THIS MORNING, CHANCES REMAIN TOO LOW TO INCLUDE IN THE TAFS.  
 

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

 
 

 
 
NEAR TERM...BCC  
SHORT TERM...BCC  
LONG TERM...LH  
AVIATION...BCC  
 
FOR MORE INFORMATION PLEASE VISIT OUR WEBSITE  
AT WEATHER.GOV/HUNTSVILLE.  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab AL Page
The Nexlab TN Page Main Text Page