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000 FXUS62 KTAE 230744 AFDTAE AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 245 AM EST MON NOV 23 2009 .SYNOPSIS... 07Z WATER VAPOR AND H4 RUC ANALYSIS SHOWING GENERALLY ZONAL UPPER LEVEL FLOW ALONG THE NORTHERN GULF COAST THIS MORNING. SOUTHERN STREAM IS QUITE PRONOUNCED WITH AN ABUNDANT HIGH LEVEL MOISTURE STREAM EXTENDING FROM CENTRAL MEXICO...ACROSS THE GULF...AND OVER THE FLORIDA PENINSULA. OTHER FEATURES OF NOTE INCLUDE BROAD RIDGING OVER THE NORTHEAST STATES AND EASTERN CANADA...AND SHORTWAVE ENERGY MOVING FROM THE INTER-MOUNTAIN WEST OVER THE HIGH PLAINS. 00Z KTLH SOUNDING SHOWED A COMPLETELY SATURATED LAYER BELOW 800MB WHICH HAS RESULTED IN WIDESPREAD LOW CLOUDS AND FOG EARLY THIS MORNING. THE FOG HAS BECOME LOCALLY DENSE IN SPOTS AND WILL BE MONITORING FOR A POSSIBLE DENSE FOG ADVISORY IF THE SIGNIFICANT VIS RESTRICTIONS EXPAND. AT THE SURFACE...HIGH PRESSURE CENTERED ALONG THE MID-ATLANTIC COAST IS RIDGING DOWN INTO THE REGION. THIS RIDGE IS RESULTING IN A LIGHT NORTH TO NORTHEAST FLOW. TEMPERATURES ARE GENERALLY IN THE 50S. THE WIDESPREAD LOWER CLOUDS WILL SLOW ANY FURTHER TEMP FALLS BEFORE SUNRISE. && .SHORT TERM (TODAY THROUGH WEDNESDAY)... TODAY...QUIET WEATHER DAY ON TAP WITH HIGH PRESSURE CONTINUING TO RIDGE DOWN INTO THE FORECAST AREA. MAIN CONCERN/ FORECAST DILEMMA WILL BE WITH THE LOWER CLOUDS/FOG THIS MORNING AND JUST HOW FAST THESE LOWER CLOUDS WILL DISSIPATE (IF AT ALL). LOOKING AT BUFKIT SOUNDINGS FROM THE GFS...NAM...AND LOCAL HIGH-RES WRF...APPEARS THAT THIS PROCESS WILL BE QUITE SLOW...ESPECIALLY NORTH OF THE FLORIA BORDER. THE LEVEL OF MOISTURE COMBINED WITH THE LOWER SUN ANGLE WILL ADD TO THE DIFFICULTY OF BREAKING THROUGH. WILL END THE REDUCED VISIBILITIES AROUND 9 AM...BUT LINGER THE LOWER CLOUDS. ALONG AND SOUTH OF THE I-10 CORRIDOR WILL KEEP THE LOWER CLOUDS THROUGH THE LATER MORNING/MIDDAY...AND THEN ALLOW FOR PARTLY CLOUDY SKIES TO DEVELOP FOR THE AFTERNOON. NORTH OF I-10 TOWARD DOTHAN/ALBANY AND TIFTON...PROFILES SUGGEST THE LOW CLOUDS HOLDING ON TILL AT LEAST EARLY AFTERNOON...AND ANY BREAKS OF SUN WILL LIKELY HOLD OFF UNTIL LATE IN THE DAY. THE CLOUDS WILL ALSO KEEP TEMPS DOWN ACROSS THE NORTH WITH LOWER/MIDDLE 60S COMMON WITH UPPER 60S AND LOWER 70S ALONG AND SOUTH OF I-10. IF THE CLOUDS HOLD ALL AFTERNOON ACROSS THE NORTH...THEN THE CURRENT FORECASTED TEMPS MAY BE A BIT OPTIMISTIC. TONIGHT...PROFILES REMAIN QUITE SATURATED NEAR THE GROUND WITH AN EXTENSIVE AREA OF DRIER AIR BETWEEN 900 AND 500MB. THIS COMBINATION SHOULD BE GOOD FOR THE DEVELOPMENT OF SHALLOW GROUND FOG AFTER SUNSET. HAVE ADDED PATCHY FOG AREA-WIDE TO THE GRIDS BY AROUND 9-10 PM THIS EVENING AND THEN EXPAND TO AREAS OF DENSE FOG AFTER MIDNIGHT. TUESDAY AND WEDNESDAY...ENERGY EXITING THE INTER-MOUNTAIN WEST IS PROGGED TO AMPLIFY ACROSS THE NORTHERN/CENTRAL PLAINS TONIGHT INTO TUESDAY MORNING. THIS AMPLIFICATION OF THE PATTERN WILL HELP DRAG THE SOUTHERN STREAM FLOW BACK TO THE NORTH INTO THE CENTRAL GULF AND SET UP A DIFFICULT FORECAST SCENARIO FOR THE MIDDLE OF THE WEEK. GLOBAL GUIDANCE SHOWING A SERIES OF SOUTHERN STREAM DISTURBANCES MOVING INTO THE CENTRAL/EASTERN GULF LATER TUESDAY THROUGH WEDNESDAY. THIS ENERGY ALOFT WILL RESULT IN SOME DEGREE OF WEAK CYCLOGENESIS/TROUGHING TO OUR SOUTH. 23/00Z RUNS OF THE GFS AND ECMWF HAVE HELD ON TO THEIR INDIVIDUAL EVOLUTIONS OF THIS SYSTEM. THE GFS KEEPS THE BEST LIFT/MOISTURE PROFILES...AND RESULTING BEST RAIN CHANCES JUST TO OUR SOUTH. THE EC ON THE OTHER HAND DEVELOPS A SLIGHTLY BETTER ORGANIZED SYSTEM/WARM FRONTAL FEATURE...AND DOES BRING A DECENT SWATH OF QPF INTO THE SOUTHEAST BIG BEND (MAINLY FROM PERRY...SOUTH AND EAST TO MAYO AND CROSS CITY). BEST FORECAST FOR NOW WILL BE TO BLEND THESE TWO SOLUTIONS AND BRING A CHANCE OF SHOWERS TO THE EASTERN BIG BEND TUESDAY NIGHT AND WEDNESDAY WITH A SLIGHT CHANCE OF SHOWERS FURTHER WEST TO TALLAHASSEE AND SOUTHERN GEORGIA. SHOWERS OR NOT...THE UPPER LEVEL DISTURBANCES SHOULD KEEP MOSTLY CLOUDY CONDITIONS OVERHEAD FOR THE EASTERN HALF OF AREA FROM TUESDAY AFTERNOON THROUGH WEDNESDAY. THE FURTHER WEST ONE GOES THE THINNER THIS CIRRUS SHOULD SHOULD BE...AND THE BETTER CHANCE FOR MID-WEEK SUN. TEMPERATURES WILL BE SEASONABLE. NAM/MET TEMPS APPEAR SIMPLY TOO COOL (DESPITE THE CLOUDS) AND HAVE TRENDED THE GRIDS CLOSER TO THE MAV NUMBERS. && .LONG TERM (THURSDAY THROUGH NEXT MONDAY)... MUCH BETTER AGREEMENT BETWEEN THE GFS AND THE ECMWF TONIGHT ON THE GENERAL FORECAST PATTERN FROM LATE WEEK THROUGH THE WEEKEND...WITH A CONSENSUS NOW FAIRLY CLOSE TO PREVIOUS FORECAST TRENDS. A FRONTAL WAVE WILL BE MOVING ACROSS THE FLORIDA PENINSULA WEDNESDAY NIGHT AND THURSDAY. BEHIND THIS DISTURBANCE...HIGH PRESSURE WILL BUILD EASTWARD ACROSS THE SOUTHEAST...SPREADING COOLER AND DRIER AIR OVER THE TRI-STATE AREA THROUGH THE WEEKEND. TEMPERATURES WILL START OUT ABOVE NORMAL AND TREND DOWNWARD TO BELOW NORMAL BY THE WEEKEND...AND POPS WILL BE BELOW NORMAL. && .AVIATION... IFR CEILINGS AND MVFR TO IFR VISIBILITIES WILL PREVAIL ACROSS THE TRI STATE AREA THROUGH MONDAY MORNING...BECOMING MVFR WITH SOME BREAKS ESPECIALLY ACROSS FLORIDA DURING THE EARLY TO MID AFTERNOON. HOWEVER...ABUNDANT LOW LEVEL MOISTURE WILL REMAIN IN PLACE...AND WIDESPREAD IFR CONDITIONS WILL DEVELOP ONCE AGAIN MONDAY NIGHT. WINDS WILL REMAIN 5 KNOTS OR LESS DURING THE AFTERNOON HOURS BECOMING NEAR CALM DURING THE NIGHT AND MORNING. && .MARINE... HIGH PRESSURE RIDGING DOWN FROM THE NORTH WILL BE IN CONTROL OF THE NORTHEAST GULF OF MEXICO THROUGH TONIGHT. SEAS ARE STILL UP AT THE BUOYS BUT SHOULD COME DOWN SLOWLY THROUGH THE DAY. A WEAK AREA OF LOW PRESSURE IS FORECAST TO DEVELOP AND MOVE TO OUR SOUTH DURING THE MID-WEEK PERIOD. WINDS AND SEAS WILL INCREASE SOMEWHAT WITH THE PASSAGE OF THIS LOW AND MAY AT TIMES APPROACH CAUTIONARY LEVELS ON WEDNESDAY. IN THE WAKE OF THIS SYSTEM THERE WILL BE A BETTER CHANCE AT A PERIOD OF CAUTIONARY NORTHWEST WINDS FROM THURSDAY INTO FRIDAY. && .FIRE WEATHER... LINGERING LOW LEVEL MOISTURE THROUGH MID WEEK WILL KEEP RELATIVE HUMIDITIES ABOVE CRITICAL LEVELS. CONDITIONS WILL NEED TO BE MONITORED CLOSELY TOWARDS THE END OF THE WEEK INTO THE WEEKEND WHEN HIGH PRESSURE BUILDS ACROSS THE SOUTHEAST U.S. SPREADING COOLER AND DRIER AIR ACROSS THE TRI-STATE AREA. && .PRELIMINARY POINT TEMPS/POPS... TALLAHASSEE 71 51 70 51 73 / 10 0 10 20 20 PANAMA CITY 70 54 71 54 72 / 10 0 10 20 20 DOTHAN 66 46 68 47 70 / 10 0 10 10 10 ALBANY 65 47 68 48 72 / 10 0 10 10 10 VALDOSTA 71 50 71 52 73 / 10 0 10 20 20 CROSS CITY 76 55 74 56 75 / 10 10 20 30 40 APALACHICOLA 71 57 69 55 72 / 10 10 10 20 20 && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...NONE. GM...NONE. && $$ SYNOPSIS/SHORT TERM/MARINE...MROCZKA LONG TERM/AVIATION/FIRE WX...DUVAL