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000 FXUS64 KMOB 262141 AFDMOB AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOBILE AL 341 PM CST THU NOV 26 2009 .SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)...A CHILLY NIGHT ON TAP WITH WIDESPREAD SITES IN OUR INLAND COUNTIES EXPECTED TO SEE OVERNIGHT LOWS NEAR 30 DEGREES. EXPECT THE NORTHERLY WINDS TO STAY UP A LITTLE BIT TONIGHT ALONG AND NEAR THE COASTAL SO OVERNIGHT LOWS WILL BE A LITTLE WARMER AROUND 40 TO MID 30S AT THESE SITES. TEMPERATURES TOMORROW SHOULD WARM INTO THE LOWER 60S MOST SITES AS THE UPPER LEVEL TROUGH SHIFTS EAST WITH RISING HEIGHTS AND WARM AIR ADVECTION (WAA) ALOFT. THE SURFACE HIGH PRESSURE SYSTEM CENTERED OVER THE SOUTHERN PLAINS WILL KEEP SURFACE WINDS NORTH TO WEST- NORTHWESTERLY AS IT SHIFTS EASTWARD. SURFACE WINDS WILL BE LIGHTER TOMORROW AS THE SURFACE GRADIENT WEAKENS AND WAA ALOFT SHUTS OFF MOMENTUM MIXING FROM THE STRONGER WINDS ABOVE THE SURFACE. ANOTHER COLD NIGHT EXPECTED FRIDAY NIGHT...HOWEVER...TEMPS AT MOST SITES SHOULD REMAIN ABOVE FREEZING AS WARM TO NEUTRAL ADVECTION OCCURS IN THE LOWER LEVELS AND RADIATIONAL COOLING IS HAMPERED BY HIGH LEVEL CLOUDS INVADING FROM THE SOUTHWEST. CLOUD COVER COMES COURTESY OF THE REMNANTS OF A CUT OFF LOW OVER BAJA CALIFORNIA BEING CAUGHT UP IN THE SOUTHERN STREAM OF THE POLAR FRONT JET AND EJECTED EAST NORTH EASTWARD ACROSS THE SOUTHEASTERN STATES. /08 JVW .LONG TERM...(SATURDAY THROUGH THURSDAY)...BY SATURDAY THE SURFACE HIGH SHIFTS EAST OF OUR AREA SIGNALING THE START OF A RETURN FLOW. HENCE, TEMPERATURES WILL MODERATE AND HUMIDITIES WILL INCREASE AT LEAST THROUGH EARLY MONDAY. THE GLOBAL SPECTRAL MODELS HAVE BEEN CONSISTENT THE PAST SEVERAL DAY IN PROJECTING A FRONTAL SYSTEM INTO OUR REGION DURING THE MONDAY TO MONDAY NIGHT TIME-FRAME. THE SOLUTIONS AMONG THE MODELS AND THEIR ENSEMBLE MEMBERS AS TO THE TIMING AND THE STRUCTURE OF THIS SYSTEM CONTINUES TO VARY CONSIDERABLY. LATEST GUIDANCE SUGGESTS THE SHORTWAVE TROUGH NOW IMPACTING THE NORTHWEST PACIFIC COAST WILL CONTINUE TO DEEPEN AS IT PROGRESSES EASTWARD. BY THE TIME IT PUSHES EAST OF THE ROCKIES ON SUNDAY THE TROUGH HAS SPLIT WITH A DEEPENING UPPER LEVEL LOW IN THE SOUTHERN STREAM OVER NORTHERN BAJA CALIFORNIA...THE TROUGH CONTINUES TO PROPAGATE EASTWARD DRIVING A SURFACE COLD FRONT ACROSS OUR REGION SOMETIME MONDAY...MAIN DYNAMICS ARE SPLIT NORTH AND SOUTH OF OUR REGION...SO CHANCE OF STRONG TO SEVERE STORMS LESSEN WITH THIS SOLUTION FOR MONDAY...MONDAY NIGHT. BUT IS HEIGHTEN FOR SOMETIME TUESDAY NIGHT THROUGH WEDNESDAY AS MODELS EJECT THE STRONG UPPER LEVEL LOW AND ASSOCIATED SOUTHERN SHORTWAVE TROUGH NORTHEASTWARD STRENGTHENING THE REMNANTS OF THE FRONTAL BOUNDARY PREVIOUSLY LEFT LINGERING ACROSS THE NORTHERN AND WESTERN GULF. ECMWF AND GFS SUGGEST RAPID CYCLOGENESIS OF A SURFACE LOW AS IT OCCLUDES AS IT MOVES ON SHORE SOMEWHERE BETWEEN SE LA AND THE FL PANHANDLE. AMPLE FORCING AND SHEER WILL BE AVAILABLE IF THE SYSTEM EVOLVES AS ADVERTISED FOR STRONG TO SEVERE CONVECTION. DEPENDING ON THE TRACK...PARTS OF OUR REGION COULD END UP IN THE WARM SECTOR. TOO MANY VARIABLES AND TOO MUCH INCONSISTENCY IN MODEL RUNS TO FULLY BUY OFF ON A FULL SOLUTION RIGHT NOW...BUT WE`LL HAVE TO CLOSELY MONITOR THE EVOLUTION OF THIS COMPLEX SYSTEM. FOR NOW THOUGH...FEEL PRETTY CONFIDENT IN THE FORECAST OF INCREASING THE CHANCE OF SHOWERS AND THUNDERSTORMS BEGINNING ON MONDAY. /08 JVW && .AVIATION...(18Z ISSUANCE) LITTLE CHANGE TO PREVIOUS FORECAST. VFR THROUGH TONIGHT WITH WINDS DROPPING OFF AFTER SUNSET AND INCREASING A BIT AFTER SUNRISE. && .MARINE...NORTHWEST WINDS WILL INCREASE AS COOL REINFORCEMENT ARRIVES WITH A DEEP UPPER TROUGH. WINDS WILL DIMINISH FRIDAY MORNING...REMAINING NORTH TO NORTHEAST INTO SATURDAY MORNING BECOMING LIGHT AND VARIABLE AS THE SURFACE HIGH CENTER ARRIVES. WIND WILL THEN VEER SOUTH SATURDAY NIGHT AS THE HIGH MOVES EAST OF THE MARINE AREA. GUIDANCE MONDAY HAS THE OUTPUT OF THE ECMWF AND GFS AT ODDS WITH EACH OTHER THEY BOTH ARE SHOWING A SURFACE LOW APPROACHING FROM THE WEST CENTRAL GMEX OFF BROWNSVILLE BUT AT DIFFERENT TIMES AND INTENSITY. LEFT THE WINDS ALONE TO KEEP THE BLEND WITH NEIGHBORS ESPECIALLY WIND DIRECTION. THE EURO WAS WEAKER AND SLOWER BRINGING THE LOW IN TO OUR WEST. WINDS INCREASING ONSHORE SUNDAY NIGHT BECOMING NORTH MONDAY NIGHT. NEXT WINDOW FOR CONVECTION IS SUNDAY NIGHT AS THE GULF OPENS UP AND WATER VAPOR RETURNS. /77 && .FIRE WEATHER...THE POST FRONTAL DRY AIRMASS ENTRENCHED OVER THE REGION ALONG WITH THE NORTHERLY SURFACE FLOW WILL CONTINUE THROUGH FRIDAY. RELATIVE HUMIDITIES HAVE FALLEN BELOW CRITICAL LEVELS FOR SEVERAL HOURS ACROSS THE WESTERN FLORIDA PANHANDLE TODAY AND ARE EXPECTED TO DO SO AGAIN TOMORROW. THE AIRMASS OVER US WILL GRADUALLY MODIFY SATURDAY AS SOUTHERLY SURFACE FLOW ESTABLISHES ITSELF OVER THE REGION. /08 JVW && .PRELIMINARY POINT TEMPS/POPS... MOBILE 34 60 37 66 / 00 00 05 05 PENSACOLA 39 61 40 66 / 00 00 05 05 DESTIN 43 60 45 63 / 00 00 05 05 EVERGREEN 31 60 34 65 / 00 00 05 05 WAYNESBORO 29 59 33 66 / 00 00 05 05 CAMDEN 33 58 34 65 / 05 05 05 05 CRESTVIEW 32 61 35 66 / 00 00 05 05 && .MOB WATCHES/WARNINGS/ADVISORIES... AL...FREEZE WARNING FROM 2 AM FRIDAY TO 7 AM FRIDAY FOR THE FOLLOWING ZONES: BUTLER...CHOCTAW...CLARKE...CONECUH...COVINGTON... CRENSHAW...ESCAMBIA...MONROE...UPPER BALDWIN...UPPER MOBILE...WASHINGTON...AND WILCOX. FL...FIRE WEATHER WATCH FROM 11 AM FRIDAY TO 4 PM FRIDAY FOR THE FOLLOWING ZONES: COASTAL ESCAMBIA...COASTAL OKALOOSA... COASTAL SANTA ROSA...INLAND ESCAMBIA...INLAND OKALOOSA... AND INLAND SANTA ROSA. FREEZE WARNING FROM 2 AM FRIDAY TO 7 AM FRIDAY FOR THE FOLLOWING ZONES: INLAND ESCAMBIA...INLAND OKALOOSA...AND INLAND SANTA ROSA. RED FLAG WARNING UNTIL 6 PM THURSDAY FOR THE FOLLOWING ZONES: COASTAL ESCAMBIA...COASTAL OKALOOSA...COASTAL SANTA ROSA... INLAND ESCAMBIA...INLAND OKALOOSA...AND INLAND SANTA ROSA. MS...FREEZE WARNING FROM 2 AM FRIDAY TO 7 AM FRIDAY FOR THE FOLLOWING ZONES: GEORGE...GREENE...PERRY...STONE...AND WAYNE. GM...SMALL CRAFT ADVISORY UNTIL 5 AM FRIDAY FOR THE FOLLOWING ZONES: COASTAL WATERS FROM DESTIN TO PENSACOLA FL OUT 20 NM... COASTAL WATERS FROM PENSACOLA FL TO PASCAGOULA MS OUT 20 NM...WATERS FROM DESTIN TO PENSACOLA FL FROM 20 TO 60 NM... AND WATERS FROM PENSACOLA FL TO PASCAGOULA MS FROM 20 TO 60 NM. && $$