105  
FXUS64 KMOB 231817 AAA  
AFDMOB  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE MOBILE AL  
1217 PM CST SUN FEB 23 2020  
   
NEAR TERM UPDATE /NOW THROUGH MONDAY/
 
BETTER MID TO HIGH  
CLOUDS OVER MUCH OF MS THIS MORNING WILL CONTINUE TO SHIFT EAST  
SOUTHEAST OVER MUCH OF SOUTHWEST AL AND NWFL THIS AFTERNOON AND  
TONIGHT IN RESPONSE TO DEEPENING MOISTURE WELL AHEAD OF A  
DEVELOPING SHORTWAVE TROF MOVING EASTWARD OVER THE SW CONUS AND  
LOWER PLAINS STATES THIS AFTERNOON AND EARLY TONIGHT THEN THE  
LOWER AND MIDDLE PLAINS STATES AND MS RIVER VALLEY MON INTO MON  
NIGHT. THIS SYSTEM BEGINS TO DAMPEN OR WEAKEN SOMEWHAT DURING THE  
DAY ON MON BEFORE BECOMING REINFORCED FROM THE NORTH OVER THE MID  
SECTION OF THE COUNTRY LATE MON INTO TUE. THE DEEPER MOISTURE  
AHEAD OF THE MAIN UPPER SYSTEM WILL BEGIN TO MOVE ACROSS THE  
NORTHERN GULF STATES AND FORECAST AREA LATE TONIGHT AND EARLY MON  
COMBINED WITH WEAK INSENTROPIC LIFT WEST OF A DEPARTING RIDGE AND  
BETTER MID LEVEL FORCING AHEAD OF THE MAIN UPPER TROF LEADING TO  
WIDESPREAD COVERAGE OF SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS  
BY MID TO LATE AFTERNOON. MODEL SOUNDINGS SUPPORT THIS REASONING  
WELL SHOWING INCREASED MOISTURE IN THE BOUNDARY LAYER DURING THE  
DAY ON MON WITH PWATS RANGING FROM 1.4 TO 1.6 INCHES BY MID TO  
LATE AFTERNOON. NEAR THE SURFACE A DEVELOPING LOW AND COLD FRONT  
ASSOCIATED WITH THE MAIN UPPER SHORT WAVE WILL ADVANCE EAST ACROSS  
THE DEEP SOUTH ON MON REACHING THE LA/TX BORDER STRETCHING  
SOUTHEAST OVER EASTERN TX BY LATE MON AFTERNOON. THE BEST SHEAR  
AND FORCING IN THE LOWER LEVELS CONTINUES TO BE OVER CENTRAL AND  
NORTHERN SECTIONS OF AL AND MS WITH LITTLE TO NO SURFACE BASED  
INSTABILITY, REMAINING MOSTLY ELEVATED OVER ALL INLAND AREAS  
DURING THE DAY ON MON. AS A RESULT STILL BELIEVE WE WILL SEE  
NUMEROUS SHOWERS WITH A FEW EMBEDDED ELEVATED THUNDERSTORMS BY MON  
AFTERNOON WITH POSSIBLE HEAVY RAIN LOCALLY IN SOME AREAS TO THE  
NORTH BECOMING THE MAIN CONCERN THROUGH MON AFTERNOON.  
TEMPERATURES WILL BE ON A WARMING TREND THROUGH MON AFTERNOON WITH  
LOWS RANGING FROM THE UPPER 40S TO LOWER 50S FOR MOST INLAND  
AREAS AND THE MIDDLE TO UPPER 50S ALONG THE IMMEDIATE COAST. 32/EE  
 

 
   
AVIATION
 
 
18Z ISSUANCE...VFR CONDITIONS THROUGH ABOUT 24.09Z FOLLOWED BY  
MOSTLY MVFR CIGS AND VISIBILITIES THROUGH 24.18Z. EXPECT  
INCREASING LOW CLOUDS FROM WEST TO EAST ON MON WITH WIDESPREAD  
SHOWERS AND A FEW EMBEDDED THUNDERSTORMS BY AFTERNOON. WINDS WILL  
BE EAST SOUTHEAST AT 4 TO 10 KTS THROUGH 24.18Z. 32/EE  
 

 
 
EXTENDED TERM /THURSDAY THROUGH SUNDAY/...A BROAD LONGWAVE TROUGH  
WILL SPAN THE EASTERN CONUS THURSDAY AND FRIDAY, BEFORE GRADUALLY  
SHIFTING TOWARD THE EASTERN SEABOARD AND WESTERN ATLANTIC THIS  
WEEKEND. A DEEP LAYER DRY AIRMASS WILL REMAIN ENTRENCHED ACROSS  
OUR FORECAST AREA THURSDAY AND FRIDAY ON THE BASE OF THE LONGWAVE  
TROUGH, AND WE EXPECT MOSTLY CLEAR SKIES AND DRY CONDITIONS TO  
PERSIST THROUGH THE LATTER HALF OF THE WEEK WITH THIS PATTERN. A  
SURFACE RIDGE OF HIGH PRESSURE LOCATED FROM SOUTHERN TX AND THE  
WESTERN GULF OF MEXICO ON THURSDAY SHOULD GRADUALLY BUILD EASTWARD  
ACROSS THE NORTH CENTRAL GULF INTO FRIDAY. TEMPERATURES ARE  
EXPECTED TO REMAIN BELOW NORMAL BOTH DAYS, WITH HIGHS ON THURSDAY  
ONLY LOOKING TO RANGE IN THE LOWER TO MID 50S, WITH SLIGHTLY  
WARMER HIGHS IN THE UPPER 50S TO LOWER 60S ANTICIPATED ON FRIDAY.  
CLEAR SKIES AND LIGHT WINDS ON THURSDAY NIGHT WILL BE SUPPORTIVE  
OF LOW TEMPERATURES NEAR OR SLIGHTLY BELOW FREEZING OVER INTERIOR  
PORTIONS OF THE FORECAST AREA. LOWS ARE CURRENTLY FORECAST TO  
RANGE BETWEEN 30-33 GENERALLY ALONG AND NORTH OF I-10 THURSDAY  
NIGHT, WHILE LOCATIONS CLOSER TO THE IMMEDIATE COAST LOOK TO RANGE  
IN THE MID 30S TO AROUND 40 DEGREES.  
 
THE MID LEVEL FLOW PATTERN TRANSITIONS NORTHWESTERLY THIS WEEKEND AS  
THE UPPER TROUGH SHIFTS ACROSS THE EASTERN SEABOARD AND WESTERN  
ATLANTIC. MEDIUM RANGE GUIDANCE HAS BEEN HINTING AT RESIDUAL  
MOISTURE WITH WEAK ASCENT ASSOCIATED WITH A SHORTWAVE TROUGH  
CLIPPING OUR AREA ON THE BACK SIDE OF THE TROUGH EITHER LATE FRIDAY  
NIGHT OR DURING THE DAY SATURDAY. CONFIDENCE ON MEASURABLE  
PRECIPITATION REMAINS LOW CONSIDERING MODEL TIMING DIFFERENCES AND  
LACK OF MOISTURE, SO WILL FOLLOW NBM TRENDS OF KEEPING POPS BELOW  
MENTIONABLE LEVELS DURING THIS TIME FRAME. THIS COULD BE SOMETHING  
TO WATCH FOR AN EVENTUAL POTENTIAL SLIGHT CHANCE OF LIGHT RAIN OVER  
OUR INTERIOR EITHER FRIDAY NIGHT OR SATURDAY. VERY LOW DEEP LAYER RH  
WITHIN NORTHWEST FLOW ALOFT WILL SUPPORT A MOSTLY CLEAR AND DRY  
FORECAST ON SUNDAY. A REINFORCING COLD FRONT ON SATURDAY FOLLOWED BY  
BUILDING SURFACE HIGH PRESSURE OVER OUR REGION MAY ALLOW HIGH  
TEMPERATURES TO DROP BACK DOWN INTO THE MID TO UPPER 50S THIS  
WEEKEND, WITH MORNING LOWS MOSTLY RANGING IN THE 30S. /21  
 
MARINE...LIGHT TO MODERATE EASTERLY WINDS BECOME SOUTHERLY BY  
MONDAY AS A COLD FRONT APPROACHES FROM THE WEST. THE COLD FRONT  
MOVES THROUGH THE MARINE AREA ON TUESDAY WITH A NORTHWESTERLY FLOW  
IN THE WAKE OF THE FRONT WHICH BECOMES STRONG BY WEDNESDAY. THE  
STRONG OFFSHORE FLOW GRADUALLY SUBSIDES THURSDAY INTO THURSDAY  
NIGHT. A SMALL CRAFT ADVISORY WILL LIKELY BE REQUIRED FOR MOST OF  
THE MARINE AREA WEDNESDAY INTO THURSDAY MORNING.  
 
PATCHY ADVECTION FOG WILL LIKELY DEVELOP OVER THE BAYS AND NEAR  
SHORE WATERS BY LATE MONDAY AFTERNOON INTO EVENING AS WARM, HUMID  
AIR AHEAD OF THE COLD FRONT MOVES OVER THE COLDER MARINE WATERS. /29  
 

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

 
 

 
 
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HTTP://WEATHER.GOV/MOB  
 
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