222
FXUS64 KMOB 161021
AFDMOB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOBILE AL
521 AM CDT WED OCT 16 2013
.SHORT TERM...(TODAY THROUGH FRIDAY)...FOR TODAY THROUGH TONIGHT...
HIGH PRESSURE RIDGE OVER THE REGION WEAKENS TODAY AND TONIGHT AS A
FRONTAL BOUNDARY DROPS SOUTH ACROSS MISSISSIPPI TODAY AND INTO THE
EXTREME NORTHWESTERN PART OF THE FCST AREA BY LATE TONIGHT. WITH
THIS...PCPN CHANCES INCREASE DURING THE SHORT TERM PERIOD...WITH NO
RAIN THIS MORNING AND THEN ISOLATED SHOWERS AND STORMS THIS AFTERNOON
OVER THE WEST-NORTHWEST ZONES (PRIMARILY WEST OF A CAMDEN THROUGH
WIGGINS LINE) AS THE FRONT APPROACHES. TONIGHT AS THE FRONT SETTLES
INTO THE FAR WEST AND NORTHWESTERN ZONES LOOK FOR CHANCE POPS TO
DEVELOP OVER MOST OF THE FCST AREA (GENERALLY ALONG AND WEST OF I-65
CORRIDOR) WITH SLIGHT CHANCE POPS EAST AND SOUTH OF I-65 IN ALABAMA
AND OVER THE WESTERN FLORIDA PANHANDLE. RAINFALL TOTALS ARE EXPECTED
TO BE LESS THAN A QUARTER OF AN INCH THROUGH TONIGHT. MOSTLY SHOWERS
EXPECTED...ALTHOUGH AN ISOLATED THUNDERSTORM CANT BE RULED OUT
ESPECIALLY OVER NORTHWEST BY LATE TONIGHT GOING INTO THURSDAY. LIGHT
SOUTH TO SOUTHWEST WINDS EXPECTED TODAY AND TONIGHT FOR MOST
LOCATIONS IN ADVANCE OF THE APPROACHING FRONT...SHIFTING TO THE WEST
OR NORTHWEST BEHIND THE FRONT OVER FAR NORTHWESTERN ZONES LATE
TONIGHT. TEMPERATURES WARMING INTO THE LOW TO MID 80S THIS AFTERNOON
WITH THE COOLER MAX TEMPS NEAR THE COAST AND WARMER TEMPS INLAND. LOW
TEMPS TONIGHT IN THE MID 60S INLAND AND UPPER 60S COASTAL. 12/DS
THURSDAY INTO FRIDAY...A SHORTWAVE SYSTEM OVER THE OHIO RIVER VALLEY
MOVES OFF TO THE NORTHEAST THURSDAY...DEFLECTED BY AN UPPER RIDGE
STRETCHING NORTHEAST FROM AN UPPER HIGH OVER THE GULF OF MEXICO. THE
SURFACE FRONT OVER NW-ERN SECTIONS OF THE FA GETS A PUSH TO OVER SE-
ERN SECTIONS OF THE FA THURSDAY NIGHT BEFORE IT'S DRIVING UPPER
DYNAMICS MOVE OFF. TEMPS REMAIN ABOVE SEASONAL...THOUGH NOT AS MUCH
AS PREVIOUS DAYS. THE CHANCE FOR PRECIP IS ABOVE SEASONAL...THOUGH
RUMBLES ARE EXPECTED TO BE LIMITED DUE TO THE LACK OF STRONG PUSH OF
THE FRONT.
LATE THURSDAY NIGHT INTO FRIDAY EVENING...MORE UPPER ENERGY MOVES
INTO AN UPPER TROUGH OVER THE EASTERN CONUS. BY FRIDAY EVENING...
THERE ARE SOME HINTS OF THE APPROACHING UPPER SYSTEM OVER WESTERN
SECTIONS OF THE LOWER...BUT THE SURFACE FRONT REMAINS STATIONARY NEAR
THE FA FOR THIS PERIOD..PROVIDING THE FOCUS FOR ISENTROPIC UPGLIDE
SHOWERS.
.LONG TERM...(FRIDAY NIGHT ON)...FRIDAY NIGHT INTO SATURDAY NIGHT...THE
SHORTWAVE ENERGY MOVING THROUGH THE WESTERN UPPER TROUGH PASSES NORTH
OF THE FA...GETTING STRETCHED/TILTED IN THE PROCESS AS THE SOUTHERN
END IS SLOWER TO MOVE THROUGH THE TROUGH AND OVER THE EASTERN RIDGE
THAN THE NORTHERN END. THIS SETS UP ISENTROPIC UPGLIDE SHOWERS ALONG
AND NORTH OF THE FRONT. WITH THE ECMWF PLACING THE FRONT A BIT
FARTHER NORTH...IT'S RAIN-SHIELD IS SIGNIFICANTLY FARTHER NORTH THAN
THE GFS. EITHER IS PLAUSIBLE...SO BLENDED THE COVERAGE FOR THE
FORECAST.
LATE SATURDAY NIGHT INTO SUNDAY NIGHT...THE PASSING SHORTWAVE PUSHES
THE SURFACE FRONT BACK SOUTH A BIT...DRYING OUT THE FA. THE ECMWF IS
A BIT MORE AGGRESSIVE IN PUSHING THE FRONT SOUTH THAN THE GFS...WITH A
COOLER SOLUTIONS FOR THE FA...ESPECIALLY OVER NORTHERN SECTIONS OF
THE FA. THIS IS ALSO ADVERTISED BY THE GFS ENSEMBLES...SO HAVE LEANED
TOWARDS THE COOLER ECMWF SOLUTIONS FOR THIS PART OF THE FORECAST.
SUNDAY NIGHT ON...GUIDANCE STARTS TO DIVERGE. BOTH THE ECMWF AND GFS
ARE ADVERTISING SOME SHORTWAVE ENERGY MOVING NORTH AROUND THE WEST
SIDE OF THE GULF. THE GFS IS ADVERTISING MORE VIGOROUS SHORTWAVES...
THUS SETTING UP MORE SIGNIFICANT UPGLIDE AHEAD OF MORE ENERGY SWING
EAST THROUGH THE WESTERN CONUS UPPER TROUGH. AS THE WESTERN ENERGY
MOVES EAST...THE GFS IS STRONGER WITH THIS ENERGY THAN THE ECMWF...
BRINGING ANOTHER SHOT OF RAIN TO THE FA MONDAY INTO MONDAY NIGHT INTO
TUESDAY NIGHT....WHILE THE ECMWF IS DRY. WITH MORE ENERGY PUSHING
INTO THE WESTERN TROUGH TUESDAY ON...A RE-ENFORCING FRONT PUSHES
ACROSS THE FA WEDNESDAY INTO THURSDAY IN BOTH THE GFS AND ECMWF. THE
ONLY DIFFERENCE IS THAT THE GFS IS ADVERTISING A WETTER SCENARIO
AHEAD OF THE FRONT THAN THE ECMWF. BY THURSDAY...BOTH SETS OF
GUIDANCE ARE ADVERTISING THE FA COMING UNDER DRY...NORTHERLY FLOW.
&&
.AVIATION...(16/12Z TAF ISSUANCE)...VFR CONDITIONS INITIALLY EXPECTED.
PATCHY LIGHT FOG POSSIBLE VERY EARLY THIS MORNING BURNING OFF BY MID
MORNING. NO RAIN FORECAST THROUGH TONIGHT AT TERMINAL
SITES...ALTHOUGH WILL BE APPROACHING FROM THE WEST AS A COLD FRONT
MOVES TOWARD THE REGION. MID TO HIGH LEVEL CLOUDS LOOK TO ADVANCE IN
FROM THE WEST THROUGH THE COURSE OF THE DAY TODAY AS THE FRONT MOVES
EASTWARD ACROSS THE LOWER MISSISSIPPI RIVER VALLEY. CLOUDS LOWER AND
PCPN CHANCES INTRODUCED TOWARD END OF THE FCST PERIOD THURSDAY
MORNING...BUT EXPECTED TO REMAIN VFR AT THIS TIME. 12/DS
&&
.MARINE...HIGH PRESSURE RIDGE OVER THE MARINE AREA WILL WEAKEN TODAY
AND TONIGHT AS A COLD FRONT APPROACHES THE COASTAL WATERS FROM THE
NORTH AND WEST. THIS FRONT WILL MOVE INTO THE COASTAL WATERS ON
THURSDAY AND THEN STALL OVER OR JUST SOUTH OF THE WATERS FRIDAY
THROUGH SUNDAY AND THEN LIFT SLOWLY BACK NORTHWARD AS A WARM FRONT
BY THE EARLY PART OF NEXT WEEK. A LIGHT EAST TO SOUTH FLOW TODAY AND
TONIGHT EXPECTED TO SHIFT TO THE NORTHWEST AND INCREASE SLIGHTLY
OVER MOST OF THE MARINE AREA BY LATE THURSDAY NIGHT IN THE WAKE OF
THE FRONT. THIS LIGHT TO MODERATE OFFSHORE FLOW IS THEN EXPECTED TO
CONTINUE THROUGH THE WEEKEND...BECOMING MORE EAST AND SOUTHEASTERLY
EARLY NEXT WEEK AS THE STALLED FRONT BEGINS TO LIFT BACK NORTH AS A
WARM FRONT. LOOK FOR AN INCREASED CHANCE FOR RAIN...SHOWERS AND
ISOLATED THUNDERSTORMS BEGINNING ON THURSDAY AND PERSISTING THROUGH
THE REMAINDER OF THE FCST PERIOD. LITTLE CHANGE IN SEAS TODAY AND
TONIGHT...BUT SLIGHTLY INCREASED SEAS EXPECTED THURSDAY AND FRIDAY
WITH THE SLIGHTLY STRONGER FLOW BEHIND THE FRONT. WINDS AND SEAS
HIGHER IN AND NEAR SHOWERS AND THUNDERSTORMS LATE THURSDAY NIGHT
INTO FRIDAY AND CONTINUING INTO EARLY NEXT WEEK. 12/DS
&&
.PRELIMINARY POINT TEMPS/POPS...
MOBILE 84 69 81 59 76 / 05 30 50 40 30
PENSACOLA 83 68 82 64 79 / 05 20 40 30 30
DESTIN 79 71 80 68 80 / 05 10 30 30 40
EVERGREEN 85 65 80 57 76 / 05 30 50 40 30
WAYNESBORO 85 66 73 54 77 / 20 30 60 30 30
CAMDEN 84 66 76 53 77 / 05 30 70 40 30
CRESTVIEW 84 64 84 62 81 / 05 20 40 40 40
&&
.MOB WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
FL...NONE.
MS...NONE.
GM...NONE.
&&
$$
12/16