271  
FXUS64 KMOB 160500 AAC  
AFDMOB  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE MOBILE AL  
1200 AM CDT TUE OCT 16 2018  
   
DISCUSSION
 
UPDATED FOR LATEST AVIATION DISCUSSION BELOW.  
 

 
   
AVIATION
 
 
06Z ISSUANCE...MOIST SOUTHERLY FLOW THROUGH TONIGHT WILL BRING  
LOW END MVFR LEVEL CIGS AS STRATUS DEVELOPS TONIGHT AND MVFR/IFR  
LEVEL VISBYS WITH FOG DEVELOPMENT. THERE IS A CONCERN IF WINDS DROP  
OFF OF LIFR OR LOWER CIGS/VISBYS OVERNIGHT. AT THIS POINT, GUIDANCE  
IS ADVERTISING WINDS STAYING STRONG ENOUGH FOR ABOVE LIFR CONDITIONS  
OVERNIGHT. DID PUT IN A TEMPO GROUP FOR LIFR CONDITIONS AT KMOB,  
WITH THIS SITE BEING SUSCEPTIBLE TO DENSE FOG FORMATION.  
 
A FRONT SAGS SOUTH ACROSS AREA TAF SITES TUESDAY NIGHT. AHEAD OF  
THE FRONT, SHOWERS AND FEW THUNDERSTORMS ARE POSSIBLE, BUT ARE NOT  
EXPECTED TO SEE COVERAGE OR INTENSITY TO IMPACT OPERATIONS.  
 
/16  
 

 
   
PREV DISCUSSION
 
/ISSUED 959 PM CDT MON OCT 15 2018/  
 
DISCUSSION...SEE UPDATED INFORMATION FOR LAND AREAS BELOW.  
 
UPDATE...SCATTERED SHOWERS AND THUNDERSTORMS OVER INTERIOR  
SOUTHEAST MS AND SOUTHWEST AL HAVE GRADUALLY BEEN DECREASING IN  
COVERAGE AND INTENSITY OVER THE PAST HOUR, THOUGH THERE HAS BEEN  
SOME NEW DEVELOPMENT OVER INTERIOR SOUTH CENTRAL AL RECENTLY. WE  
HAVE ADJUSTED POPS FOR THE REST OF THE EVENING, KEEPING THE BEST  
CHANCE (40-50%) FOCUSED OVER INTERIOR SOUTHWEST AND SOUTH CENTRAL  
AL, WITH LOWER CHANCES (20-30%) FARTHER SOUTHWEST ACROSS THE REST  
OF SOUTHWEST AL AND SOUTHEAST MS. WE HAVE ALSO ADDED MENTION OF  
PATCHY FOG LATE TONIGHT ACROSS PORTIONS OF THE INTERIOR NORTHWEST  
FL PANHANDLE AND SOUTHWEST/SOUTH CENTRAL AL. HOURLY TEMPERATURES  
AND DEWPOINTS WERE ALSO ADJUSTED TO BETTER REFLECT THE LATEST  
TRENDS. /21  
 
PREV DISCUSSION... /ISSUED 645 PM CDT MON OCT 15 2018/  
 
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.  
 
AVIATION...  
00Z ISSUANCE...MOIST SOUTHERLY FLOW THROUGH TONIGHT WILL BRING  
LOW END MVFR LEVEL CIGS AS STRATUS DEVELOPS TONIGHT AND MVFR/IFR  
LEVEL VISBYS WITH FOG DEVELOPMENT. THERE IS A CONCERN IF WINDS  
DROP OFF OF LIFR OR LOWER CIGS/VISBYS OVERNIGHT. AT THIS POINT,  
GUIDANCE IS ADVERTISING WINDS STAYING STRONG ENOUGH FOR ABOVE  
LIFR CONDITIONS OVERNIGHT. A FRONT SAGS SOUTH ACROSS AREA TAF  
SITES LATE TUESDAY. AHEAD OF THE FRONT, SHOWERS AND FEW  
THUNDERSTORMS ARE POSSIBLE, BUT ARE NOT EXPECTED TO SEE COVERAGE  
OR INTENSITY TO IMPACT OPERATIONS.  
 
/16  
 
PREV DISCUSSION... /ISSUED 356 PM CDT MON OCT 15 2018/  
 
NEAR TERM /NOW THROUGH TUESDAY/...THE UPPER LEVEL PATTERN REMAINS  
GENERALLY UNCHANGED OVER THE LOCAL AREA THROUGH THE NEAR TERM,  
WITH HIGH PRESSURE OVER THE GULF OF MEXICO AND A TROUGH OVER THE  
NORTHERN CONUS RESULTING IN A DEEP-LAYER WEST-SOUTHWEST FLOW. AT  
THE SURFACE, A STRONG COLD FRONT CURRENTLY EXTENDS FROM SOUTHEAST  
TEXAS UP INTO THE OHIO VALLEY AND A SURFACE RIDGE REMAINS PLANTED  
OVER THE WESTERN ATLANTIC AND NORTHEASTERN GULF. AHEAD OF THIS  
FRONT AND BETWEEN THESE TWO FEATURES, SOUTHERLY FLOW CONTINUES TO  
PUMP GULF MOISTURE INTO THE DEEP SOUTH AND SOUTHEASTERN STATES,  
WITH PWATS HOLDING STEADY AROUND 1.8 TO 2.0 INCHES. THE FRONT  
WEAKENS AS IT APPROACHES THE LOCAL AREA LATE TONIGHT, STALLING  
BRIEFLY BEFORE PUSHING THROUGH COMPLETELY DURING THE DAY TUESDAY.  
EXPECT SCATTERED SHOWERS TO CONTINUE DEVELOPING ALONG AND AHEAD OF  
THE FRONT, WITH THE BEST RAIN CHANCES OVER THE NEXT 24 HOURS  
LOCATED GENERALLY WEST OF I-65 AND ALONG THE COAST. SHALLOW ASCENT  
AND MODEST INSTABILITY (DAYTIME MLCAPES AROUND 1000-1250 J/KG)  
SHOULD LIMIT THE POTENTIAL FOR THUNDER, THOUGH A FEW RUMBLES  
CANNOT BE RULED OUT IN THE HEAVIER CELLS DURING LATE AFTERNOON  
HOURS. TEMPERATURES ARE A BIT TRICKY THIS PERIOD AS THEY WILL  
DEPEND HEAVILY ON THE TIMING OF THE FRONT. AT THIS TIME, HAVE LOWS  
TONIGHT IN THE LOW TO MID 60S FOR OUR NORTHWESTERNMOST COUNTIES,  
GENERALLY ALONG/NORTHWEST OF A LINE FROM DEMOPOLIS, AL TO  
WAYNESBORO, MS. ELSEWHERE, LOWS REMAIN IN THE UPPER 60S AND LOWER  
70S. A SIMILAR NORTHWEST-SOUTHEAST GRADIENT SETS UP TUESDAY AS  
HIGHS RANGE FROM MID TO UPPER 70S NORTH/WEST OF I-65, LOW TO MID  
80S ALONG I-65, AND MID TO UPPER 80S SOUTH/EAST OF I-65. /49  
 
SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...A LARGE  
WEST-EAST ORIENTATED UPPER LEVEL HIGH PRESSURE SYSTEM WILL REMAIN  
OVER THE GULF OF MEXICO, EXTREME SOUTHEAST STATES, AND THE  
WESTERN ATLANTIC. HOWEVER, THE ORIENTATION WILL SHIFT AS THE  
EASTERN HALF OF THE HIGH PRESSURE MOVES SOUTHWARD DUE TO AN UPPER  
LEVEL TROUGH EXITING THE NORTHEAST CONUS AND MOVING OVER THE  
NORTHERN ATLANTIC, WHILE THE WESTERN HALF SHIFTS NORTHWARD AS A  
BUILDING RIDGE OVER THE MISSISSIPPI RIVER VALLEY IN THE WAKE OF  
THE EXITING TROUGH. THE SURFACE COLD FRONT ALONG THE COAST WILL  
MOVE OFFSHORE MIDWEEK INTO THURSDAY AS A STRONG 1034MB SURFACE  
HIGH PRESSURE SYSTEM BUILDS NORTH OF THE REGION. MAINLY ISOLATED  
SHOWERS TUESDAY EVENING WILL DISSIPATE OVERNIGHT INTO WEDNESDAY,  
FOLLOWED BY RAIN-FREE CONDITIONS THROUGH THE REAMINDER OF THE  
SHORT TERM. /22  
 
LONG TERM /FRIDAY THROUGH MONDAY/...THE ENTIRE LARGE UPPER LEVEL  
HIGH PRESSURE SYSTEM WILL MOVE SOUTHWARD FRIDAY AND INTO THE  
WEEKEND AS A SECOND STRONGER UPPER LEVEL TROUGH DIGS SOUTHEAST  
FROM SOUTH CENTRAL CANADA OVER THE ENTIRE EASTERN CONUS. THE UPPER  
LEVEL TROUGH WILL THEN REMAIN OVER THE EASTERN CONUS THROUGH THE  
REAMINDER OF THE LONG TERM. THE SURFACE HIGH PRESSURE SYSTEM  
ACROSS THE SOUTHEAST STATES WILL SHIFT EASTWARD AS ANOTHER STRONG  
COLD APPROACHES FROM THE NORTH LATE IN THE WEEK. THE COLD FRONT  
IS FORECAST TO PASS THROUGH THE FORECAST AREA ON SATURDAY.  
ISOLATED TO SCATTERED SHOWERS AND PERHAPS A FEW STORMS ARE  
EXPECTED AHEAD OF AND ALONG THE COLD FRONT FRIDAY THROUGH SATURDAY  
EVENING, FOLLOWED BY RAIN-FREE CONDITIONS THROUGH THE REAMINDER OF  
THE LONG TERM. /22  
 
MARINE...LIGHT TO OCCASIONALLY MODERATE SOUTHEAST FLOW AND SEAS  
AROUND 2 FEET PERSIST THROUGH TUESDAY AS A COLD FRONT APPROACHES  
FROM THE NORTHWEST. THE FRONT PUSHES THROUGH THE MARINE AREA TUESDAY  
NIGHT, BRINGING A MODERATE NORTHEAST FLOW AND SEAS INCREASING TO 3  
TO 5 FEET WEDNESDAY/THURSDAY. WINDS THEN VEER TO EASTERLY ON FRIDAY  
BEFORE ANOTHER FRONT ON SATURDAY BRINGS A STRONGER OFFSHORE FLOW AND  
BUILDING SEAS OVER THE WEEKEND. /49  
 

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

 
 

 
 
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HTTP://WEATHER.GOV/MOB  
 
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