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000 FXUS62 KTAE 290558 AFDTAE AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 205 AM EDT WED OCT 29 2008 .SYNOPSIS...WITH THE STRONG AND COLD SFC RIDGE CONTINUING TO BUILD IN FROM THE WEST...SFC WINDS ARE CONTINUING TO SLACKEN ACROSS THE REGION...ALLOWING TEMPS TO BEGIN THEIR STEADY FALL UNDER THE CLEAR SKIES. AS OF 11 PM EDT...SOME INTERIOR LOCATIONS IN THE CWA HAVE ALREADY DROPPED INTO THE UPPER 30S (TALLAHASSEE...QUINCY...AND CROSS CITY) WITH THE COLDEST TEMP OF 36 NOW REPORTED AT VALDOSTA. WITH THESE VALUES ALREADY IN THE BOOKS BEFORE MIDNIGHT...THE CURRENT FREEZE WARNING APPEARS TO BE IN VERY GOOD SHAPE...AND WILL LEAVE THE TABLE BELOW IN FOR REFERENCE. HERE ARE SOME CLIMATOLOGICAL STATISTICS REGARDING FREEZES AND RECORD LOW TEMPS... THIS MORNING (OCTOBER 29TH) TALLAHASSEE...................31 SET IN 1987 APALACHICOLA..................41 SET IN 1976 PANAMA CITY 5N (COOP SITE)....36 SET IN 2001 HEADLAND AL...................32 SET IN 1952 ALBANY 3 SE (COOP SITE).......30 SET IN 1987 ALL TIME RECORD LOWS FOR OCTOBER TALLAHASSEE...................30 SET IN 1973...1989 AND 1993 APALACHICOLA..................33 SET IN 1993 PANAMA CITY 5N (COOP SITE)....33 SET IN 1989 HEADLAND AL...................26 SET IN 2001 ALBANY 3 SE (COOP SITE).......28 SET IN 1989 AVERAGE FALL FIRST FREEZE PERIOD OF RECORD TALLAHASSEE (AIRPORT).........NOVEMBER 19TH 1948 TO PRESENT TALLAHASSEE (DOWNTOWN)........DECEMBER 6TH 1885 TO 1961 APALACHICOLA..................DECEMBER 14TH 1975 TO PRESENT PANAMA CITY 5N................DECEMBER 10TH 1972 TO PRESENT HEADLAND AL...................NOVEMBER 13TH 1950 TO PRESENT ALBANY 3SE....................NOVEMBER 19TH 1902 TO PRESENT OVER THE COASTAL WATERS...ALTHOUGH SCA CONDITIONS ARE NO LONGER BEING OBSERVED...DO EXPECT THE SCEC LEVEL (15 TO 20 KT) WINDS TO CONTINUE ACROSS THE OFFSHORE LEGS OVERNIGHT...AS THE COLD AIR ADVECTION SHOULD REMAIN FAIRLY STRONG. && .SHORT TERM...THE ABOVE MENTIONED SFC RIDGE WILL REMAIN IN CONTROL ACROSS THE CWA DURING THE NEXT FEW DAYS...AS IT VERY SLOWLY SLIDES E-NE TO A POSITION CENTERED NEAR THE NC/SC BORDER BY FRIDAY AFTERNOON. ALTHOUGH IT MAY INITIALLY WEAKEN BELOW 1030 MB TODAY AND TONIGHT...IT IS PROGGED TO RE-BUILD TO BETWEEN 1030 AND 1035 MB ON THURSDAY AND FRIDAY. AT UPPER LEVELS...THE STEEP TROF DOWN THE EASTERN SEABOARD WILL QUICKLY DE-AMPLIFY...AS THE POTENT LOW PRESSURE SYSTEM HEADS FURTHER NE INTO CANADA...LEAVING US WITH MORE ZONAL FLOW AFTER TODAY. WITH RISING HEIGHTS AND PLENTY OF SUNSHINE ...A GRADUAL WARMING TREND IS EXPECTED...BUT IT MAY BE SEVERAL MORE DAYS BEFORE CLIMO LEVEL TEMPS RETURN. WE ARE STILL CONCERNED ABOUT LOW TEMPS ONCE AGAIN FOR TONIGHT...BUT AT THIS TIME...EXPECT LOWS TO BE GENERALLY A COUPLE OF DEGREES WARMER ACROSS THE BOARD. PARTS OF THE INTERIOR SE FL BIG BEND MAY BRIEFLY REACH" onClick="return popup(this, 'notes')">REACH FREEZING...BUT WILL CURRENTLY PLAN ON USING AREAS OF FROST OVER THE INTERIOR OF THE CWA. && .LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)... PATTERN TO BEGIN THE UPCOMING WEEKEND WILL FEATURE A RATHER "BAGGY" LOOK TO THE MID-LEVEL HEIGHTS ACROSS THE SOUTHEAST WITH VERY WEAK TROUGHING OVERHEAD. ELONGATED SURFACE RIDGING WILL STILL BE IN PLACE FROM THE MID-ATLANTIC STATES TO THE NORTHERN GULF COAST PROVIDING A LIGHT NORTHEAST FLOW TO THE AREA. STILL SHOULD BE DRY TO START THIS PERIOD WITH THE FLOW AROUND THE SURFACE HIGH KEEPING THE BEST MOISTURE TO OUR EAST AND SOUTH ACROSS THE FL PENINSULA. GFS/ECMWF BOTH INDICATING A PIECE OF MID-LEVEL ENERGY DIVING SOUTH ALONG THE MISSISSIPPI VALLEY AROUND THE EASTERN PERIPHERY OF STRONG RIDGING OVER THE WESTERN PLAINS. THIS ENERGY IS PROGGED TO REACH THE NORTHERN GULF OF MEXICO DURING SATURDAY AND CUT OFF OVER OR JUST SOUTH OF THE FORECAST AREA. FROM THIS POINT ON THERE ARE TWO SCHOOLS OF THOUGHT ON THE EVOLUTION OF THIS CUT-OFF ENERGY. THE GFS IS INDICATING A DEEPER AND LESS PROGRESSIVE SYSTEM WHICH HOLDS IN THE VICINITY THROUGH MONDAY NIGHT. THE ECMWF IS SHOWING A LESS ORGANIZED AND MORE PROGRESSIVE SYSTEM WHICH HAS A BRIEF STAY OVER THE EASTERN GULF AND WHOSE INFLUENCE EXITS EAST BY THE END OF SUNDAY. TO SOME DEGREE THIS FASTER AND WEAKER SCENARIO HAS SOME SUPPORT FROM THE LATEST 00Z CANADIAN WHICH IS QUITE PROGRESSIVE WITH ITS SOLUTION. DESPITE THE DIFFERENCES IN PATTERN ALOFT THE SURFACE PATTERNS ARE QUITE SIMILAR. SURFACE HIGH PRESSURE RIDGING INTO THE AREA FROM THE NORTH SHOULD BE RE-ENFORCED BY EARLY NEXT WEEK AS ANOTHER STRONG HIGH DROPS SOUTHEAST THROUGH THE GREAT LAKES. WILL USE AN ENSEMBLE APPROACH THIS WEEKEND AND EXIT THE SYSTEM NOT AS FAST AS THE ECMWF BUT FASTER THAN THE GFS. ALLOWING FOR THIS SOMEWHAT SLOWER SOLUTION...WILL HAVE TO INTRODUCE SOME SLIGHT/CHANCE POPS TO THE SOUTHEAST HALF OF THE AREA SUNDAY AND MONDAY... MAINLY SOUTHEAST OF A LINE FROM TIFTON TO BAINBRIDGE AND PANAMA CITY. UNDER THIS SCENARIO THE GFS WOULD INDICATE A BROAD AREA OF DEEP LAYER Q-G FORCING OVER THE EASTERN ZONES AND IS ALSO SHOWING SOME FAIRLY SIGNIFICANT ISENTROPIC UPGLIDE THROUGH THE LOWER/MID-LEVELS. THIS LIFT WOULD BE FED BY ABUNDANT ATLANTIC MOISTURE ADVECTING WESTWARD ALONG THE SOUTHERN PERIPHERY OF THE SURFACE RIDGE. THE RESULT WOULD BE MAINLY SHALLOW AND FAST MOVING SHOWERS. FORECAST DETAILS AS TO WHERE THIS MOISTURE/FORCING WILL BE MAXIMIZED ARE IMPOSSIBLE AT THIS TIME WITH THE TIMING/EVOLUTION DIFFERENCES WITHIN THE GLOBAL MODELS. WITH THIS IN MIND WILL AVOID DETAILS AND KEEP THE GRIDS RATHER BROAD. ALL GUIDANCE HAS THE SYSTEM WELL TO THE NORTHEAST BY TUESDAY NIGHT WITH STACKED RIDGING RETURNING TO MUCH OF THE SOUTHEAST. && .AVIATION...VFR CONDITIONS WILL PREVAIL AT ALL TERMINALS THROUGH THE FORECAST PERIOD WITH CLEAR TO MOSTLY CLEAR SKIES. HIGH PRESSURE WILL CONTINUE TO BUILD EAST INTO THE SOUTHEASTERN STATES THROUGH THE DAYLIGHT HOURS ON WEDNESDAY. WITH THIS HIGH IN CLOSE PROXIMITY... WINDS WILL BE NOTICEABLY LIGHTER ACROSS THE AREA THAN ON TUESDAY WITH GENERALLY UNDER 10 MPH AT ALL TERMINALS. && .MARINE...EXPECT WINDS AND SEAS TO DIMINISH STEADILY TODAY AS THE RIDGE BUILDS IN JUST TO THE NW OF THE WATERS...BUT THIS BREAK IN THE RECENTLY TOUGH CONDITIONS FOR MARINERS WILL LIKELY BE SHORT LIVED...AS THE SFC HIGH REBUILDS AND STRENGTHENS TO OUR NE THURSDAY NIGHT AND FRIDAY. THIS WILL LIKELY RESULT IN ANOTHER PERIOD OF CAUTIONARY TO ADVISORY CONDITIONS ACROSS THE COASTAL WATERS FOR THE END OF THE WEEK. && .FIRE WEATHER...WITH PLENTY OF DRY AIR IN PLACE...RED FLAG CONDITIONS LOOK FAIRLY CERTAIN ACROSS ALL OF THE FL BIG BEND AND PANHANDLE TODAY AND THURSDAY...SO WILL UPGRADE THURSDAY`S WATCH TO A WARNING. OVER AL AND GA...ALTHOUGH AFTERNOON RELATIVE HUMIDITIES WILL BE VERY LOW...LIGHT WINDS SHOULD PRECLUDE RED FLAG CONDITIONS. && .PRELIMINARY POINT TEMPS/POPS... TALLAHASSEE 63 33 70 42 73 / 0 0 0 0 0 PANAMA CITY 63 39 72 47 73 / 0 0 0 0 0 DOTHAN 62 36 71 41 73 / 0 0 0 0 0 ALBANY 62 34 70 39 72 / 0 0 0 0 0 VALDOSTA 65 32 71 40 72 / 0 0 0 0 0 CROSS CITY 65 32 74 41 76 / 0 0 0 0 0 && .TAE WATCHES/WARNINGS/ADVISORIES... AL...FREEZE WARNING UNTIL 7 AM CDT THIS MORNING ALL ZONES. GA...FREEZE WARNING UNTIL 8 AM EDT THIS MORNING ALL ZONES. FL...FREEZE WARNING UNTIL 8 AM EDT /7 AM CDT/ THIS MORNING ALL ZONES...EXCEPT IMMEDIATE COAST. FROST ADVISORY UNTIL 8 AM EDT /7 AM CDT/ THIS MORNING ALONG THE COAST. RED FLAG WARNING THIS AFTERNOON ALL ZONES. RED FLAG WARNING THURSDAY AFTERNOON ALL ZONES. GM...NONE. && $$ AVIATION/FIRE WX/LONG TERM...MROCZKA PUBLIC/MARINE...GOULD