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000 FXUS62 KTAE 300544 AFDTAE AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 200 AM EDT THU OCT 30 2008 .SYNOPSIS...THE INITIAL SFC RIDGE WHICH BROUGHT SOME RECORD COLD LOW TEMPERATURES TO THE REGION ON WEDNESDAY MORNING IS NOW CENTERED JUST OFF TO OUR NW...WITH CLEAR SKIES AND NEAR CALM WINDS ONCE AGAIN SET UP ACROSS THE CWA. THIS WILL ALLOW FOR GOOD RADIATIONAL COOLING CONDITIONS OVERNIGHT...BUT STILL EXPECT LOW TEMPERATURES TO BE GENERALLY A COUPLE OF DEGREES WARMER THAN LAST NIGHT. ALSO...WITH T/TD SPREADS EXPECTED TO BE SMALLER AS WELL...MANY INTERIOR LOCATIONS COULD RECEIVE A FAIRLY THICK FROST BY SUNRISE. OVER THE COASTAL WATERS...WINDS ARE STILL GENERALLY IN THE 5 TO 10 KT RANGE OUT OF THE N WITH 1 TO 2 FT SEAS...BUT STILL EXPECT THE 10 TO 15 KT NE SURGE TO DEVELOP LATER TONIGHT...AS THE SFC RIDGE BEGINS TO REBUILD AND STRENGTHEN TO OUR NE. && .SHORT TERM...THE REBUILDING AND STRENGTHENING TO THE NE OF THE COLD SFC RIDGE WILL BE THE FOCUS OF THE SYNOPTIC PATTERN ACROSS THE SE U.S. FOR MUCH OF THE NEAR TERM PERIOD. ONLY SLOWLY MODERATING TEMPS ARE EXPECTED EACH DAY...BUT THE FAIR AND DRY WX WILL PERSIST. BY SATURDAY...HOWEVER...THE FCST WILL BEGIN TO BECOME MORE COMPLEX...AS A FAIRLY SMALL AND WEAK SHORTWAVE WHICH IS NOW TRAVERSING WYOMING... WILL CONTINUE TO DIG SE ALL THE WAY TO THE NORTHERN GULF COAST... WHERE IT IS PROGGED TO BECOME A CUTOFF UPPER LOW. IT WILL INITIALLY BE STARVED FOR MOISTURE...SO DO NOT EXPECT ANY SENSIBLE WX ON SATURDAY...BUT THIS COULD CHANGE BY THE END OF THE WEEKEND AND EARLY NEXT WEEK...POTENTIALLY MAKING FOR A VERY CHALLENGING POP AND TEMP FCST OVER THE CWA. && .LONG TERM (SUNDAY THROUGH THURSDAY)... LOOKING AT THE THE LATEST 00Z GFS AND CANADIAN WE FIND EXTREMELY CLOSE FORECASTS THROUGH TUESDAY. THE ECMWF REMAINS A FASTER OUTLIER IN THE EASTERN PROGRESSION OF THIS SYSTEM AND THE ASSOCIATED DYNAMICS. THIS EASTWARD PROGRESSION IS A RESULT OF THE EC PRODUCING A DEEPER AND MORE POTENT TROUGH EXITING THE INTER-MOUNTAIN WEST DURING THE EARLY PART OF NEXT WEEK WHICH ACTS AS A KICKER TO KEEP THE PATTERN MOVING. WHILE THE LATEST OPERATIONAL GFS IS LESS AMPLIFIED WITH THIS SYSTEM TO THE WEST...ITS 12Z ENSEMBLES WHERE CLOSER TO THE EC SOLUTION. WITH RESPECT TO BOTH THE LATEST 00Z GUIDANCE AND THE 12Z ENSEMBLES WILL RUN A BLEND BETWEEN THE GFS AND ECMWF FOR THE SUNDAY THROUGH TUESDAY PERIOD AND THEN GO CLOSE TO THE GFS SOLUTION FOR THE MID-WEEK PERIOD AS THE PATTERNS ARE ROUGHLY THE SAME. SHORTWAVE ENERGY DROPPING SOUTH ALONG THE MS VALLEY HAS CUT-OFF INTO AN UPPER LOW FEATURE OVER THE NORTHEAST GULF OF MEXICO BY SUNDAY MORNING. AT THE SURFACE...THE OLD SURFACE RIDGE ALONG THE EAST COAST WILL BE RE-ENFORCED AS STRONG 1035MB HIGH PRESSURE DROPS THROUGH THE GREAT LAKES TO THE NORTHEAST STATES. DEEP LAYER Q VECTOR PLOTS INDICATING LARGE SCALE LIFT ASSOCIATED WITH THE UPPER LEVEL LOW EXPANDS ACROSS THE FORECAST AREA DURING SUNDAY. GFS ALSO CONTINUES TO INDICATED FAIRLY HEALTHY LOW/MID LEVEL ISENTROPIC UPGLIDE ACROSS THE NORTH-CENTRAL FL PENINSULA AND INTO THE FORECAST AREA. WITH PLENTY OF DRY LOW LEVEL AIR IN PLACE ACROSS THE NORTHWEST HALF OF THE AREA WOULD EXPECT RAIN TO HAVE A TOUGH TIME REACHING THE SURFACE. HOWEVER...FURTHER SOUTH AND EAST THE LOW LEVELS WILL BE MORE CONDUCIVE AS ATLANTIC MOISTURE ADVECTS WESTWARD ALONG THE SOUTHERN PERIPHERY OF THE SURFACE RIDGE. FOR THIS REASON THE CHANCES OF SCT SHOWERS OR AREAS OF LIGHT RAIN ARE INCREASING FOR SUNDAY AFTERNOON INTO MONDAY OVER PORTIONS OF NORTHERN FLORIDA AND EXTREME SOUTHERN GEORGIA. STILL A FEW SPRINKLES ARE NOT OUT OF THE QUESTION OVER OUR WESTERN ZONES AS WELL. MEX IS NOT INDICATING THIS YET...BUT MAY SEE TEMPS STAYING ON THE COOL SIDE (60S) ON SUNDAY AND MONDAY OVER PORTIONS OF THE AREA AS THE UPPER LEVEL SYSTEM TRIES TO PRECIPITATE INTO THE DRIER LOW LEVEL AIR. UPPER LEVEL LOW AND ASSOCIATED DYNAMICS BEGIN TO LIFT OUT TO THE NE TUESDAY. WILL BEGIN HEDGING THE HIGHEST POPS BY THIS POINT UP TO THE I-75 CORRIDOR IN GA...ESPECIALLY WITH THE POSSIBILITY OF A SURFACE WAVE ATTEMPTING TO FORM ALONG THE GA COAST. FINALLY FOR WED/THU WE FIND STACKED RIDGING RETURNING TO OUR AREA WITH FAIR AND SEASONABLE CONDITIONS. && .AVIATION...VFR CONDITIONS UNDER MOSTLY CLEAR SKIES WILL CONTINUE THROUGH THE TAF PERIOD. HIGH PRESSURE WILL SLIDE TO THE NORTH OF THE AREA THROUGH THE DAY TURNING WINDS TO THE NORTHEAST. THIS NORTHEAST FLOW MAY BRING JUST ENOUGH MOISTURE WESTWARD TO RESULT IN A FEW-SCT CU FIELD ACROSS THE SOUTHEAST FL BIG BEND DURING THE AFTERNOON AND EVENING...HOWEVER THIS MOISTURE IS EXPECTED TO REMAIN SOUTH AND EAST OF THE KVLD AND KTLH TERMINALS THROUGH THURSDAY EVENING. && .MARINE...AS THE SFC RIDGE REGAINS A CENTRAL PRESSURE BACK INTO THE 1035 MB RANGE OVER THE CAROLINAS TONIGHT AND FRIDAY MORNING...THE TIGHTENING GRADIENT ACROSS OUR COASTAL WATERS SHOULD AT LEAST SUPPORT SCEC LEVEL CONDITIONS WITH A SHORTER PERIOD OF SCA CONDITIONS POSSIBLE AS WELL...ESPECIALLY FURTHER OFFSHORE. THE MARINE FCST OVER THE WEEKEND IS VERY COMPLEX...AND WILL BE HIGHLY DEPENDENT ON THE STRENGTH OF A NEW WEDGE TO THE NE AND A POTENTIAL SFC TROF OVER THE GULF OF MEXICO. && .FIRE WEATHER...RED FLAG CONDITIONS WILL CONTINUE ACROSS THE FL BIG BEND AND PANHANDLE TODAY...AND IT NOW APPEARS THERE IS A GOOD CHANCE OF LONG DURATIONS OF SUB 35 PERCENT ON FRIDAY AS WELL. HOWEVER... SINCE THERE IS STILL SOME UNCERTAINTY ABOUT HOW MUCH LOW LEVEL MOISTURE WILL PUSH IN FROM THE NE...WILL JUST ISSUE A FIRE WX WATCH FOR FRIDAY AT THIS TIME. && .PRELIMINARY POINT TEMPS/POPS... TALLAHASSEE 70 40 72 43 74 / 00 00 00 05 10 PANAMA CITY 72 46 73 46 75 / 00 00 00 05 10 DOTHAN 70 40 71 41 74 / 00 00 00 05 10 ALBANY 68 38 70 39 74 / 00 00 00 05 10 VALDOSTA 69 40 71 42 74 / 00 00 00 05 10 CROSS CITY 72 40 75 44 75 / 00 00 00 05 10 && .TAE WATCHES/WARNINGS/ADVISORIES... AL...FROST ADVISORY IN EFFECT UNTIL 7 AM CDT THIS MORNING ALL ZONES. GA...FROST ADVISORY IN EFFECT UNTIL 8 AM EDT THIS MORNING ALL ZONES. FL...FROST ADVISORY IN EFFECT UNTIL 8 AM EDT /7 AM CDT/ THIS MORNING ALL ZONES AWAY FROM THE COAST. RED FLAG WARNING THIS AFTERNOON ALL ZONES. FIRE WX WATCH FRIDAY AFTERNOON ALL ZONES. GM...NONE. && $$ AVIATION/FIRE WX/LONG TERM...MROCZKA PUBLIC/MARINE...GOULD