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000 FXUS62 KTAE 021005 AAA AFDTAE AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE TALLAHASSEE FL 500 AM EDT SUN NOV 02 2008 ...UPDATED TO INCLUDE FIRE WEATHER DISCUSSION... .SYNOPSIS... LOOKING AT THE 07Z WATER VAPOR AND H4 RUC ANALYSIS ACROSS NORTH AMERICA SHOWS A RATHER MESSY UPPER LEVEL PATTERN. FROM WEST TO EAST WE FIND AN AMPLIFIED SYSTEM/TROUGH JUST BEGINNING TO COME ASHORE FROM CALIFORNIA TO BRITISH COLUMBIA. NORTHERN STREAM FLOW IS RIDING NORTHWARD AROUND THE EASTERN SIDE OF THIS SYSTEM AND FLOWING UP AND OVER A SHARP RIDGE ACROSS THE INTER-MOUNTAIN WEST. PRECEDING THIS RIDGE WE FIND A SHORTWAVE MOVING QUICKLY EASTWARD ALONG THE CANADIAN/U.S BORDER APPROACHING THE UPPER MS VALLEY. THE FLOW THEN DIPS INTO A BROADER TROUGH COVERING MUCH OF EASTERN CANADA AND NEW ENGLAND. CLOSER TO HOME WE FIND A SHORTWAVE TROUGH THAT DROPPED SOUTH INTO THE NORTH-CENTRAL GULF OF MEXICO ON SATURDAY HAS CLOSED OFF TO OUR WEST. WATER VAPOR IMAGERY IS SHOWING MID/UPPER LEVEL MOISTURE ASSOCIATED WITH THIS SYSTEM FINALLY BEGINNING TO SPREAD EAST OVER THE FORECAST AREA. AT THE SURFACE...1028MB RIDGE AXIS CONTINUES TO RESIDE JUST TO OUR NORTH AND NORTHWEST. GRADIENT ON THE SOUTHERN PERIPHERY OF THIS RIDGE IS PROVIDING NORTHEAST TO NORTH FLOW TO THE AREA. THE TRAJECTORY OF THE NORTHEAST FLOW OFF THE ATLANTIC IS BRINGING MORE ABUNDANT LOW LEVEL MOISTURE INTO THE EASTERN FLORIDA BIG BEND WITH DEWPOINTS IN THE MIDDLE 50S...WHILE AREAS FURTHER OFF TO THE NORTH AND WEST ARE CURRENTLY IN THE UPPER 30S TO MIDDLE 40S. && .SHORT TERM (TODAY THROUGH TUESDAY)... TODAY...UPPER LEVEL LOW REACHES IT DEEPEST POINT AROUND 573DM EARLY THIS MORNING CENTERED OFF THE FLORIDA PANHANDLE COAST. GFS/ECMWF BOTH SHOWING THIS LOW EDGING VERY SLOWLY EASTWARD ACROSS THE AREA THROUGH THE DAY WHILE BEGINNING TO FILL A BIT. IT NOW APPEARS THAT THE OPPORTUNITY FOR A SPRINKLE ACROSS THE WESTERN HALF OF THE AREA IS BECOMING BRIEF AT BEST AS THE MAIN SYNOPTIC LIFT ON THE EASTERN SIDE OF THE LOW ASSOCIATED WITH HEALTHY MID-LEVEL Q-VECTOR CONVERGENCE EXITS THESE ZONES BY EARLY AFTERNOON. IN FACT...WITH THE SURFACE RIDGE TO THE NORTH SUPPLYING A CONTINUOUS FEED OF DRY LOW LEVEL AIR...FEELING INCREASINGLY CONFIDENT THAT MEASURABLE PRECIPITATION WILL JUST NOT BE ABLE TO MATERIALIZE WEST OF A LINE FROM AROUND ALBANY TO BAINBRIDGE TO PANAMA CITY. WILL KEEP SPRINKLES IN THE FORECAST...ALTHOUGH EVEN THIS MIGHT BE OVERDONE. BETTER CHANCES FOR SHOWERS/AREAS OF LIGHT RAIN WILL BE DEVELOPING THROUGH THE DAY EAST AND SOUTH OF A LINE LINE FROM ROUGHLY VALDOSTA TO TALLAHASSEE AND PANAMA CITY. THESE ZONES WILL SEE MORE FAVORABLE CONDITIONS FOR SHOWERS WITH BETTER LOW LEVELS MOISTURE AND MORE ALIGNMENT WITH THE LARGE SCALE LIFT. ALSO WILL BE SEEING SOME ENHANCEMENT TO THE OVERALL LIFT ASSOCIATED WITH MID-LEVEL ISENTROPIC UPGLIDE FROM THE NORTH-CENTRAL FL PENINSULA INTO THE EASTERN FL BIG BEND AND EASTERN MARINE ZONES. WEAK SURFACE TROUGH FORECAST BY ALMOST ALL THE GUIDANCE OVER THE EASTERN GULF OF MEXICO WILL PROVIDE SOME ADDITIONAL LOW LEVEL FOCUS AND MAY ACTUALLY RESULT IN DECENT RAINFALL COVERAGE OVER THE WATER BY THE AFTERNOON AND EVENING HOURS. GFS/ECMWF ARE STILL SHOWING SHOWALTER INDICES AROUND ZERO FOR LATER THIS MORNING INTO THE EVENING HOURS OVER THE MARINE ZONES AND EXTENDING UP TO AROUND THE COASTLINE OF THE FL BIG BEND. THESE NUMBERS SUGGEST A BETTER INSTABILITY PROFILE ABOVE THE SURFACE AND WOULD NOT BE SURPRISED TO SEE A FEW EMBEDDED THUNDERSTORMS. TONIGHT...UPPER LEVEL LOW CENTER CONTINUES TO MOVE SLOWLY NORTHEAST REACHING THE GA/SOUTH CAROLINA COASTLINE EARLY MONDAY MORNING. THIS EVOLUTION WILL ALSO EXIT THE BEST SYNOPTIC AND ISENTROPIC LIFT EAST OF OUR ZONES FAIRLY EARLY. STRONG 1035-1040MB SURFACE HIGH PRESSURE DROPPING SOUTHEAST FROM THE GREAT LAKES TO NEW ENGLAND WILL ACT TO RE-ENFORCE THE RIDGING ALONG THE EAST COAST AND BACK INTO THE SOUTHEASTERN STATES. AT THE SAME TIME...AS WEAK UPPER LEVEL HEIGHT FALLS BEGIN TO PUSH OFF THE SOUTHEAST COAST...GUIDANCE IS SHOWING A SHARPENING OF AN INITIALLY WEAK SURFACE TROUGH OFF THE NE FL COAST. WHILE SOME AMPLIFICATION IS LIKELY...THE GFS IS LIKELY ON THE EXTREME SIDE. HOWEVER...EVEN A MORE MODEST SHARPENING WILL ACT TO TURN OUR WINDS MORE TO THE NORTH ACROSS THE EASTERN ZONES AS THE GRADIENT TIGHTENS BETWEEN THIS TROUGH AND THE RIDGE TO THE NORTH. THIS MORE NORTHERLY FLOW WOULD SCOUR OUT SOME OF THE LOW LEVEL MOISTURE IN PLACE OVER THE EAST...AND WITH THE LOSS OF SYNOPTIC LIFT WILL NEED TO TAPER POPS BACK DURING THE SECOND HALF OF THE NIGHT. MONDAY THROUGH TUESDAY...UPPER LEVEL FEATURE CONTINUES TO FILL BECOMING MORE OF A BROAD TROUGH ALONG THE SOUTHEAST COAST. LOW LEVEL PATTERN IS NOT CHANGING MUCH THROUGH THIS PERIOD WITH A GENERAL NORTH-NORTHEAST FLOW BETWEEN THE SURFACE TROUGH OFF THE SE COAST AND THE RIDGE TO OUR NORTHWEST. THIS FLOW WILL BE BRINGING PLENTY OF DRY LOW LEVEL AIR INTO THE WESTERN 2/3RDS OF THE FORECAST AREA AND RESULT IN A DRY FORECAST. SEEMS TO BE A BIT TOUGHER FORECAST MONDAY AND MONDAY NIGHT ALONG THE SUWANNEE RIVER VALLEY/I-75 CORRIDOR AS THE MOISTURE GRADIENT IS LIKELY TO BE RATHER TIGHT IN THIS VICINITY. HOWEVER...THE TREND HAS BEEN TOWARD A DRIER FORECAST. WILL LEAVE A SLIGHT CHANCE POP UP FOR OUR FAR EASTERN ZONES CLOSER TO THE UPPER TROUGH AXIS AND AVAILABLE ATLANTIC MOISTURE. LATER MONDAY NIGHT INTO TUESDAY GLOBAL MODELS ARE SHOWING THE AMPLIFIED SURFACE TROUGH CLOSING OFF INTO A HEALTHY LOW SE OF THE CAROLINA COASTLINE. AS THIS LOW PULLS FURTHER NORTH IT WOULD ACT TO CUT OFF ANY LINGERING INFLUX OF ATLANTIC MOISTURE INTO OUR EASTERN ZONES AND WILL LEAVE THE INHERITED SILENT/DRY POP GRID ALONE. && .LONG TERM...(WEDNESDAY THROUGH NEXT SUNDAY)... VERY LITTLE CHANGE FROM LAST NIGHT`S THINKING ABOUT THE EXTENDED PERIOD...AS UPPER LEVEL RIDGING WHICH WILL BUILD IN FROM THE W BEHIND THE UPPER LOW...WILL COMBINE WITH A WEAK CONTINENTAL SFC HIGH TO PROVIDE THE REGION WITH A COUPLE OF FAIR...WARM...AND DRY DAYS ON WED AND THU. HIGH TEMPS SHOULD CLIMB ABOVE CLIMO LEVELS INTO THE UPPER 70S TO EVEN THE LOWER 80S ACROSS THE WARMER INTERIOR LOCATIONS. THIS RIDGING WILL BE SHORT LIVED...HOWEVER...AS THE NEXT COLD FRONT WILL BE QUICKLY ON ITS HEELS...AND SHOULD MOVE THROUGH THE REGION ON FRI AND FRI NIGHT. CONFIDENCE OF THIS TIMING IS INCREASING AS WELL...WITH THE GFS AND ECMWF BOTH COMING INTO VERY GOOD AGREEMENT ON THEIR LATEST RUNS. POPS MAY BE A BIT CHALLENGING OUT AHEAD OF THIS FRONT...AS RETURN FLOW MOISTURE WILL BE LIMITED AND SHORT LIVED...BUT WILL LIKELY BE JUST SUFFICIENT ENOUGH FOR A PERIOD OF SCT SHOWERS OVER MUCH OF THE AREA...SO WILL PLAN ON 30 PERCENT POPS AT THIS TIME. BEHIND THE COLD FRONT...EXPECT SOME DECENT COLD AIR ADVECTION...AND THE GFS BIAS CORRECTED GRIDS ARE PICKING UP ON THIS FASTER THAN THE MEX GUIDANCE WHICH IS WEIGHTED TOO HEAVILY TOWARDS CLIMO THIS FAR OUT...SO WILL STICK NEAR THE CURRENT GRIDS WHICH HAVE HIGHS IN THE UPPER 60S TO THE LOWER 70S FROM NW TO SE. AT NIGHT...EXPECT LOWS TO DROP BELOW CLIMO LEVELS ON SAT AND SUN MORNINGS...BUT NO FREEZING OR NEAR FREEZING TEMPS ARE EXPECTED AT THIS TIME...AS THIS AIRMASS WILL NOT BE NEARLY AS COLD AS THE RECORD BREAKING AIRMASS FROM LAST WEEK. && .MARINE... FAIRLY TIGHT GRADIENT ACROSS THE MARINE ZONE BETWEEN HIGH PRESSURE TO OUR NORTHWEST AND A DEVELOPING SURFACE TROUGH OFF THE SOUTHEAST COAST WILL KEEP NORTHEASTERLY FLOW GOING INTO THE DAY ON MONDAY. WINDS AND SEAS NEAR CAUTIONARY LEVELS THIS MORNING WILL DIMINISH A BIT THIS AFTERNOON ONLY TO COME BACK UP TO CAUTIONARY LEVELS AGAIN TONIGHT THROUGH MONDAY NIGHT. THE STRONGEST WINDS AND HIGHEST SEAS WILL BE MOST PREVALENT ACROSS THE OFFSHORE WATERS. AN UPPER LEVEL DISTURBANCE CROSSING THE WATERS THROUGH TONIGHT WILL BRING INCREASING CHANCES FOR SHOWERS AND A FEW THUNDERSTORMS WITH RAIN CHANCES DIMINISHING ON MONDAY. WINDS AND SEAS WILL DROP BELOW HEADLINE CRITERIA ON TUESDAY AND REMAIN LOW THROUGH THE MIDDLE PORTION OF THE WEEK AS THE SURFACE RIDGE TO OUR NORTH MOVES SOUTH AND EAST OVER THE FORECAST WATERS. && .AVIATION... VFR CONDITIONS ARE HOLDING AT ALL OF THE TAF SITES EARLY THIS MORNING...WITH A LARGER BAND OF AC MOVING IN FROM THE EAST OVER MUCH OF SW AND SC GA AND PARTS OF THE FL BIG BEND AND PANHANDLE. THUS FAR...THIS AC DECK IS A BIT HIGHER THAN LAST NIGHT AT THIS TIME (BETWEEN 9 AND 11 KFT)...AND ALSO SEE NO EVIDENCE OF ANY LOWER SC OR CU MIXED IN AT THIS TIME...EVEN ALONG THE NE FL AND SE GA COASTLINES WHERE IT SET UP WELL LAST NIGHT. THEREFORE...IT NOW LOOKS LIKE ALL OF THE TAF SITES WILL SPEND MORE TIME AT VFR OVERNIGHT THAN EARLIER EXPECTED...BUT ONCE THE ISENTROPIC LIFT KICKS IN FROM THE DEVELOPING UPPER LEVEL LOW...LOWER CIGS COULD DEVELOP IN A HURRY OVER THE EASTERN TAF LOCATIONS...JUST NOT CONFIDENT THAT THIS WILL OCCUR BEFORE SUNRISE. DURING THE DAYTIME...AS THE UPPER LOW GATHERS MORE MOISTURE...ISOLATED TO SCATTERED SHOWERS ARE PROGGED TO DEVELOP ACROSS EASTERN PORTIONS OF THE CWA...BUT AT THIS TIME...EXPECT ANY TSTMS TO BE CONFINED TO THE COASTAL WATERS AND THE SE FL BIG BEND... SO WILL LEAVE THESE OUT OF OUR CURRENT TAF PACKAGE. && .FIRE WEATHER... A DEVELOPING UPPER LEVEL LOW PRESSURE SYSTEM OVER THE NORTHEAST GULF OF MEXICO WILL BRING INCREASING MOISTURE TO THE REGION TODAY...WITH A CHANCE OF SHOWERS ACROSS MAINLY EASTERN SECTIONS OF THE AREA. ISOLATED THUNDERSTORMS WILL ALSO BE POSSIBLE ACROSS THE SOUTHEASTERN FLORIDA BIG BEND AND ALONG THE IMMEDIATE COAST OF THE WESTERN BIG BEND. A FEW SHOWERS WILL LINGER INTO TONIGHT...BEFORE DRIER AIR RETURNS TO MUCH OF THE REGION ON MONDAY AND TUESDAY. WARMER CONDITIONS ARE EXPECTED ON WEDNESDAY AND THURSDAY...BEFORE A COLD FRONT BRINGS THE NEXT CHANCE OF SHOWERS TO THE TRI STATE AREA ON FRIDAY. MUCH COOLER AND DRIER AIR IS EXPECTED TO BUILD INTO THE SOUTHEAST OVER THE WEEKEND...AND IT MAY TAKE SEVERAL DAYS BEFORE RED FLAG OR NEAR RED FLAG CONDITIONS RETURN TO THREATEN THE FORECAST AREA. && .PRELIMINARY POINT TEMPS/POPS... TALLAHASSEE 73 53 76 52 76 / 30 20 10 10 10 PANAMA CITY 73 57 75 57 75 / 20 10 10 0 10 DOTHAN 73 51 74 50 74 / 10 10 0 10 10 ALBANY 74 51 74 51 74 / 10 10 10 10 10 VALDOSTA 73 55 73 53 73 / 40 20 10 10 10 CROSS CITY 74 56 76 54 76 / 50 20 10 10 10 && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...NONE. GM...NONE. && $$ SYNOPSIS/SHORT TERM/MARINE...MROCZKA AVIATION/LONG TERM/FIRE WX...GOULD