290 FXUS64 KBMX 231758 AAB AFDBMX AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE BIRMINGHAM AL 1158 AM CST SUN NOV 23 2014 .UPDATE... AVIATION DISCUSSION && .DISCUSSION... UPDATED FORECAST TO REFLECT CURRENT RADAR AND TEMP/DEWPOINT TRENDS. WIDESPREAD SHOWERS AND SCATTERED THUNDERSTORMS CURRENTLY MOVING NORTH THROUGH CENTRAL ALABAMA. SEEN AN INCREASE IN COVERAGE OVER THE LAST HOUR ACROSS SOUTHERN COUNTIES. NOT CERTAIN HOW THIS WILL AFFECT THE AIRMASS ACROSS THE AREA LATER THIS AFTERNOON...AS THE WARM FRONT IS STILL TO OUR SOUTH. LOOKING AT THE 16Z SURFACE ANALYSIS...A WARM FRONT STRETCHES EAST TO WEST ALONG THE ALABAMA/FLORIDA STATE LINE BEFORE ANGLING TO THE NORTHWEST NEAR EVERGREEN TOWARD MERIDIAN. DEWPOINTS SOUTH OF THIS LINE ARE IN THE MID TO UPPER 60S AND LOWER 70S. TO THE NORTH...DEWPOINTS IN THE LOWER 60S COOL TO THE MID TO UPPER 50S SOUTH TO NORTH ACROSS CENTRAL ALABAMA. ON RADAR...A CONVECTIVE BAND...ARCHING FROM NEAR MERIDIAN SOUTH SOUTHEASTWARD TO PENSACOLA FL...IS MOVING TO THE NNE. DEWPOINTS FALL INTO THE LOW 60S BEHIND THIS BAND...AND THERE IS A WIND SHIFT FROM SSE TO SSW BEHIND THE LINE. THIS APPEARS TO BE OUR EFFECTIVE DRYLINE. AS THIS CONVECTIVE BAND ROTATES TO THE NNE...IT WILL PUSH THE MOIST AIR SOUTH OF THE WARM FRONT NORTHWARD INTO SOUTHERN PORTIONS OF CENTRAL ALABAMA THIS AFTERNOON. THE POTENTIAL FOR SEVERE STORMS WILL OCCUR IN BETWEEN THE WARM FRONT LIFTING NORTHWARD AND THE CONVECTIVE BAND MOVING NNE INTO THE AREA. GENERAL TIMING...HAS THE CONVECTIVE BAND NEAR MONTGOMERY BETWEEN 12-2PM. GIVEN THE UNCERTAINTY OF HOW QUICKLY THE WARM FRONT LIFTS NORTHWARD...HARD TO DETERMINE HOW NARROW OR WIDE A CORRIDOR OF INSTABLITY WE WILL BE DEALING WITH BETWEEN THE TWO FEATURES. WILL BE WATCHING DEWPOINTS CLOSELY ACROSS THE SOUTHERN EXTENT OF CENTRAL ALABAMA TO ASSESS ANY CHANGES TO HAZARDS AND THE FORECAST. NORTH OF THE WARM FRONT...EXPECT WIDESPREAD SHOWERS AND OCCASIONAL THUNDERSTORMS. HEAVY RAINFALL AND A STRONG WIND GUSTS WILL BE POSSIBLE. 14 && .AVIATION... 18Z TAF DISCUSSION. WIDESPREAD SHOWERS AND SCATTERED THUNDERSTORMS AFFECTING CENTRAL ALABAMA TERMINALS THIS AFTERNOON...REDUCING VIS TO LIFR AT TIMES. IN ADDITION...CIGS ARE IFR TO MVFR. THESE CONDITIONS WILL PERSIST UNTIL RAIN PUSHES NORTH AND EAST OF THE AREA. TIMED THE BACK EDGE OF THE RAIN SHIELD COMING ACROSS EAST MS TO APPROXIMATE RAIN ENDING TIMES AT TERMINALS. HOWEVER...THERE COULD BE LIGHT RAINFALL BEHIND THIS LINE...BUT CURRENT TRACK AS IT MOVING NORTH OF ALL TERMINALS. THERE MIGHT BE A PERIOD OF BKN CIGS AS RAIN ENDS...BUT LOW STRATUS WILL RETURN THIS EVENING. GIVEN THE MOIST GROUND CONDITIONS...EXPECT FOG TO DEVELOP AS WELL...MIGHT HAVE TO ADJUST VIS DOWN BELOW MVFR. WINDS WILL CONTINUE TO GUST THIS AFTERNOON...BECOMING SOUTHERLY AT ALL TERMINALS. THE EXCEPTION IS ANB WHERE EASTERLY WINDS HAVE PERSISTED TODAY...AND A SHIFT TO THE SOUTHEAST IS EXPECTED. TONIGHT...WINDS WILL GRADUALLY BECOME SOUTHWESTERLY AT ALL TERMINALS AROUND 10KTS. AS WINDS INCREASE FROM THE WEST MONDAY MORNING...CIGS WILL BEGIN TO LIFT. HOWEVER...KEPT MVFR CIGS IN THROUGH AT LEAST 18Z. HAVE INTRODUCED 12-15KT WINDS FOR MONDAY MORNING. SOME GUIDANCE IS INDICATING HIGHER GUSTS AND THESE VALUES COULD BE INCREASED WITH FUTURE FORECASTS. 14 && .PREV DISCUSSION... /ISSUED 635 AM CST SUN NOV 23 2014/ HAVE DONE A QUICK UPDATE OF THE GRIDS/TEXT PRODUCTS TO PUSH BACK THE TIME OF SEVERE POTENTIAL A LITTLE TO 10AM-6PM. THE MORE MOIST UNSTABLE AIR HAS BEEN SLOW TO COME IN TO CENTRAL ALABAMA THIS MORNING. THINK THAT THE EASTERLY FLOW HAS AIDED IN THIS NON TRANSITION AS OF YET. SO HAVE ADJUSTED TS POTENTIAL BY A FEW HOURS. HAVE ALSO REFRESHED HOURLY TEMPS/DEW POINTS WHILE AT IT. UPDATE ALREADY OUT. 08/MK && .PREV DISCUSSION... /ISSUED 456 AM CST SUN NOV 23 2014/ THIS MORNING THE SURFACE RIDGE THAT YESTERDAY STRETCHED ALONG THE EASTERN SEABOARD HAS NOW MOVED OFF INTO THE ATLANTIC OCEAN. ACROSS CENTRAL ALABAMA WE STILL HAVE A GENERALLY EAST FLOW. IN THE UPPER LEVELS...A SHORTWAVE WAS SWINGING ACROSS TEXAS. LATEST SATELLITE DATA INDICATES THAT THE TROUGH HAS STARTED TO TURN TO THE NORTHEAST AND SHOULD CONTINUE TO THE NORTHEAST TODAY GIVING A NEGATIVE TILT TO THE UPPER TROUGH AS IT MOVES ACROSS ARKANSAS AND THEN INTO KENTUCKY/TENNESSEE BY LATE THIS AFTERNOON. AT THE SAME TIME...A SURFACE LOW HAS DEVELOPED ACROSS SOUTH TEXAS AND HAS STARTED TO PUSH NORTHEAST AS WELL IN RESPONSE TO THE SHORTWAVE AND SHOULD MOVE IT INTO NORTH LOUISIANA THIS MORNING AND INTO MISSOURI/WESTERN KENTUCKY BY THIS EVENING. THIS SURFACE LOW HAS ALREADY STARTED TO PULL WARMER/MOIST AIR AND RAIN SHOWERS ACROSS PORTIONS OF ALABAMA AND INTO GEORGIA WELL AHEAD OF THE DRY LINE BOUNDARY THAT IS EXPECTED TO PUSH THROUGH DURING THE DAY TODAY. THEN TONIGHT INTO MONDAY MORNING...A COLD FRONT IS EXPECTED TO SWEEP THROUGH BEHIND IT TO HELP COOL THINGS OFF FOR THE WEEK. AS FAR AS PRECIPITATION WITH THIS EVENT...WE WILL CONTINUE TO SEE ELEVATED SHOWERS AND THEN LATER THIS MORNING THUNDERSTORMS WILL BEGIN TO SPREAD NORTHWARD ACROSS CENTRAL ALABAMA...BUT THIS ACTIVITY SHOULD REMAIN ELEVATED FOR THE EARLY MORNING WITH STILL EXPECTED EASTERLY FLOW AT THE SURFACE. WE SHOULD BEGIN TRANSITIONING DURING THIS TIME FRAME. AS WE MOVE INTO THE LATER MORNING HOURS ON SUNDAY...THE LATEST TRENDS IN MODEL DATA ARE FOCUSING IN OUR BEST OPPORTUNITY FOR INSTABILITY AND SURFACE BASED CONVECTION AS THE DRY LINE MOVES ACROSS. ALTHOUGH WE ARE STILL TALKING ABOUT A WINDOW OF 7AM TO 4PM...THE BEST CHANCES LOOK TO BE 11AM THROUGH 4PM...CLOSER TO THE BOUNDARY PASSAGE...BUT SOME STRONG TO SEVERE ACTIVITY BEFORE THAT IS NOT TOTALLY OUT OF THE QUESTION IF THE WARM FRONT PROGRESSES NORTHWARD QUICKER AND WE GET CELLS FIRING UP AHEAD OF THE LINE. THE QUESTION WILL BE HOW LONG BEFORE OUR DRY LINE ARRIVAL WILL OUR SURFACE FLOW GIVE WAY TO SOUTHERLY FLOW. THIS MAY MAKE THE DIFFERENCE IN REALIZING OUR INSTABILITY POTENTIAL AND EXACTLY HOW FAR NORTH THE HIGHER LOW LEVEL INSTABILITY VALUES REACH. WITH THE HEAT OF THE DAY POTENTIAL FOR ARRIVAL...WE SHOULD NOT HAVE AS MUCH OF A PROBLEM GETTING THE REQUIRED INSTABILITY. AGAIN...THINK HEAVY RAIN WILL BE LESS WIDESPREAD AND MORE LOCALLY STORM INFLUENCED AS THE LINE SHOULD MOVE AND NOT LINGER. SOME WRAP AROUND PRECIPITATION IS POSSIBLE AS THE SYSTEM PULLS OUT OF THE AREA THROUGH MONDAY. ALSO...ANOTHER UPPER SHORTWAVE TROUGH WILL MOVE ACROSS LATE TUESDAY INTO WEDNESDAY THAT COULD BRING A FEW SHOWERS ACROSS THE SOUTHEAST. HOWEVER...IT IS EXPECTED TO BE WELL OUT OF THE AREA BY THURSDAY FOR THANKSGIVING DAY...WITH DRY WEATHER EXPECTED FOR THE REMAINDER OF THE WEEK INTO NEXT WEEKEND. A DRY FRONT IS EXPECTED TO MOVE IN ON THANKSGIVING. ALTHOUGH STILL DRY...THE LATEST MODEL RUN IS SHOWING A WEAKER BOUNDARY THAT MAY STALL AND FIZZLE OUT. NO MAJOR TEMPERATURES CHANGES ARE EXPECTED WITH THIS SYSTEM FOR NOW. 08/MK && .PRELIMINARY POINT TEMPS/POPS... GADSDEN 63 53 61 35 53 / 100 30 20 10 10 ANNISTON 64 54 63 37 54 / 100 30 20 10 10 BIRMINGHAM 66 55 62 38 54 / 100 30 20 0 10 TUSCALOOSA 68 53 62 37 57 / 100 20 10 0 0 CALERA 67 55 63 38 55 / 100 20 10 0 10 AUBURN 66 59 68 41 56 / 100 30 10 0 10 MONTGOMERY 71 58 69 40 58 / 100 20 10 0 10 TROY 72 57 71 40 57 / 100 20 10 0 20 && .BMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 08/58