482  
FXUS64 KMOB 142055  
AFDMOB  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MOBILE AL  
355 PM CDT TUE AUG 14 2018  
   
NEAR TERM /NOW THROUGH WEDNESDAY/
 
14.12Z UPPER AIR ANALYSIS  
SHOWS LITTLE OVERALL CHANGE TO THE GEO-POTENTIAL HEIGHT FIELDS  
ALOFT OVER THE PAST DAY WITH A TROF AXIS OVER THE OH RIVER VALLEY  
GRADUALLY EASING EASTWARD. MEANWHILE, AN UPPER RIDGE PERSISTS  
SOUTH OF THE LA COAST WHILE NEXT TROF TO MOVE EAST WAS POSITIONED  
OVER THE CENTRAL PLAINS. AN ASSESSMENT OF DEEP MOISTURE SHOWS  
PWAT'S NEAR 2 INCHES OVER THE CENTRAL GULF COAST. CONSIDERING  
MOISTURE, DESTABILIZATION OF THE LOCAL AIRMASS AND THE CONTINUED  
PASSAGE OF MID LEVEL IMPULSES IN THE HIGHER LEVEL NORTHWEST FLOW  
BETWEEN THE TWO PRESSURE SYSTEMS RECENTLY MENTIONED, STORMS ARE  
FORECAST TO DEVELOP THRU THE REMAINDER OF THE AFTERNOON. LATEST  
RADAR TRENDS SHOW ISOLATED TO SCATTERED ACTIVITY HUGGING THE  
EASTERN BORDER OF THE FORECAST AREA AND WESTWARD NEAR THE I-10  
CORRIDOR. SOME OF THE STORMS LIKELY WILL PRODUCE BRIEF STRONG  
CONVECTIVE DOWNBURSTS (40 MPH OR HIGHER) UPON COLLAPSE OF ANY OF  
THE STRONGEST CORES. FREQUENT LIGHTNING AND LOCALLY HEAVY RAINS  
ALSO LIKELY IN THE STRONGEST STORMS.  
 
TONIGHT, WILL MAINTAIN A PERSISTENCE TYPE APPROACH ON  
SHOWERS/STORMS. WILL CARRY A SMALL PROBABILITY INTO THE EVENING TO  
ACCOUNT FOR LINGERING ACTIVITY CARRYING OVER FROM THE AFTERNOON.  
PATCHY LATE NIGHT FOG DEVELOPMENT ALSO POSSIBLE, ESPECIALLY IN AREAS  
THAT SEE AFTERNOON AND EARLY EVENING RAINFALL. ON WEDNESDAY, THE  
LATEST GLOBAL GUIDANCE IS CONSISTENT ON SHOWING LOWERING MID LEVEL  
HEIGHTS SPREADING EASTWARD ACROSS THE LOWER/MID MS RIVER VALLEY  
ASSOCIATED WITH NEXT TROF MOVING OUT OF THE PLAINS. MID LEVEL  
RIDGING INTO THE LOCAL AREA SHRINKS, WHILE BECOMING MORE AMPLIFIED  
OVER THE WESTERN GULF AND UP INTO TX. A CHANCE OF SHOWERS AND STORMS  
IS MAINTAINED DURING THE HEAT AND INSTABILITY OF THE DAY WEDNESDAY.  
/10  
   
SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/
 
WEDNESDAY  
NIGHT THROUGH THURSDAY, UPPER LEVEL HIGH PRESSURE OVER THE  
SOUTHERN PLAINS/NORTHWESTERN GULF CONNECTS WITH UPPER LEVEL HIGH  
PRESSURE SPREADING WEST OVER THE NORTHERN GULF FROM THE CARIBBEAN.  
THIS ORGANIZES A LOW LEVEL RIDGE THAT HAS BUILT WEST OVER THE  
NORTHERN GULF AND BRINGS A MORE ORGANIZED ONSHORE FLOW OFF THE  
GULF. MOISTURE LEVELS THAT HAD DIPPED A BIT ON WEDNESDAY RETURN TO  
THEIR PREVIOUS "SOUPY" LEVELS (PRECIP H20 LEVELS RISING TO 2" OR  
GREATER OVER THE FORECAST AREA) AS GULF MOISTURE RETURNS. AN UPPER  
TROUGH SHIFTS EAST OVER THE MISSISSIPPI RIVER, WITH THE SOUTHERN  
END BISECTING THE NORTHERN GULF RIDGE LATER WEDNESDAY INTO  
WEDNESDAY NIGHT. IN CONCERT WITH THE HIGH MOISTURE LEVELS, SCATTERED  
TO NUMEROUS TSRA ARE EXPECTED OVER THE AREA FOR THURSDAY.  
GREATEST MOISTURE RETURN IS INDICATED OVER EASTERN PORTIONS OF THE  
FORECAST AREA, SO HAVE PLACED HIGHEST POPS THIS SECTION OF THE  
FORECAST AREA. HIGHER RAIN COVERAGE EAST WILL LEAD TO HIGHER HIGH  
TEMPS WEST AND A W-E GRADIENT OF HIGH TEMPS THURSDAY (AROUND 90  
EAST TO NEAR 95 WEST). WHEN COMBINED WITH THE HIGHER MOISTURE  
LEVELS, HIGHER HEAT INDICES ARE EXPECTED WEST (101 TO 107F),  
MAINLY WEST OF THE ALABAMA RIVER. EAST OF THE RIVER, HEAT INDICES  
OF 98 TO 102 ARE ADVERTISED IN THE GUIDANCE.  
 
THURSDAY NIGHT THROUGH FRIDAY, ENERGY MOVING OVER THE MISSISSIPPI  
RIVER DIGS A DEEPER UPPER TROUGH (AS COMPARED TO PREVIOUS DAYS  
GUIDANCE) CENTERED JUST EAST OF THE MISSISSIPPI RIVER (FARTHER  
WEST THAN PREVIOUS DAYS). THIS POSITION DIRECTS A SERIES OF  
SHORTWAVE IMPULSES OVER/NEAR THE FORECAST AREA AND BRINGS  
SCATTERED DAYTIME THUNDERSTORMS TO THE AREA. TEMPS A BIT COOLER  
THAN WEDNESDAY ARE EXPECTED AS SUBSIDENCE FROM THE WEAKENING UPPER  
RIDGE OVER THE NORTHERN GULF DECREASES, BUT ARE STILL EXPECTED TO  
RISE INTO THE LOW 90S. HEAT INDICES OF 100 TO 105 ARE EXPECTED  
AREA-WIDE WITH THE SEASONABLY HOT TEMPERATURES TOPPING OUT IN THE  
LOW 90S.  
 
NOT TO FORGET OVERNIGHT LOWS, THE INCREASED MOISTURE LEVELS ALONG  
WITH INCREASED UPPER SUBSIDENCE INITIALLY WILL KEEP TEMPERATURES  
FROM DROPPING BELOW A 72 TO 76 DEGREE RANGE INLAND FROM THE COAST.  
ONSHORE WARM FLOW OFF THE GULF WILL BRING OVERNIGHT LOW IN THE 75  
TO 79 DEGREE RANGE EACH NIGHT.  
 
LASTLY FOR THE SHORT TERM, WITH DAYTIME INSTABILITY LEVELS HIGH  
ENOUGH FOR STRONG TO MARGINALLY SEVERE STORMS (MLCAPES RISING TO  
AROUND 2000J/KG EACH DAY), SOME OF THE STRONGER STORMS CAN BRING  
WIND GUSTS TOPPING 40 MPH OR HIGH AS THEY COLLAPSE.  
 
/16  
   
LONG TERM /SATURDAY THROUGH TUESDAY/
 
SATURDAY THROUGH SUNDAY,  
SHORTWAVE ENERGY MOVES THROUGH THE EASTERN CONUS UPPER TROUGH,  
SHIFTING IT EAST. ULTIMATELY THE AXIS MOVES EAST OF THE FORECAST  
AREA MONDAY. UNTIL THEN, INCREASED UPPER SUPPORT AND HIGH MOISTURE  
LEVELS WILL BRING SCATTERED TO NUMEROUS DAYTIME THUNDERSTORMS  
AREA WIDE. INCREASED CLOUD COVER AND RAIN COOLING WILL DROP  
EXPECTED DAYTIME HIGH TEMPS A FEW DEGREES FROM PREVIOUS DAYS, TO  
THE 88 TO 91 DEGREE RANGE. MONDAY ON, GUIDANCE IS ADVERTISING AN  
UPPER LEVEL RIDGE BUILDING BACK WEST FROM THE CARIBBEAN OVER THE  
NORTHERN GULF. CHANCES OF RAIN DECREASE EARLY IN THE COMING WORK  
WEEK, WITH DAYTIME HIGHS INCHING UPWARD FROM THE WEEKEND. WITH THE  
INCREASED SUBSIDENCE FROM THE UPPER RIDGE BRINGING A DRIER  
AIRMASS TO THE AREA MONDAY ON, OVERNIGHT LOWS SEE A SEVERAL DEGREE  
DROP FROM THE WEEKEND AS THE WORK WEEK PROGRESSES.  
 
/16  
 

 
   
MARINE
 
LARGE SURFACE HIGH OVER THE SOUTHWEST ATLANTIC PERSISTS  
AND RIDGES WESTWARD INTO THE GULF FOR SEVERAL DAYS. THIS MAINTAINS A  
SOUTH TO SOUTHWEST PREVAILING FLOW. SEAS 1 TO 2 FEET. WINDS, WAVES  
AND SEAS LOCALLY HIGHER IN AND NEAR STORMS. /10  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
MOBILE 73 93 74 91 74 91 74 91 / 20 30 20 50 20 50 20 60  
PENSACOLA 76 90 77 89 77 90 76 89 / 30 50 20 50 20 50 20 50  
DESTIN 77 89 78 89 78 88 78 87 / 30 50 40 40 10 50 20 50  
EVERGREEN 73 94 73 91 73 92 73 91 / 30 30 10 60 20 50 20 60  
WAYNESBORO 72 94 72 94 72 92 73 90 / 20 30 10 40 20 50 20 60  
CAMDEN 72 95 73 92 73 92 73 90 / 20 30 10 50 20 50 20 60  
CRESTVIEW 73 92 73 89 73 91 73 90 / 30 50 30 60 20 50 20 60  
 

 
   
MOB WATCHES/WARNINGS/ADVISORIES
 
 
AL...NONE.  
FL...NONE.  
MS...NONE.  
GM...NONE.  

 
 

 
 
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