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000 FXUS62 KTAE 150648 AFDTAE AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 248 AM EDT WED OCT 15 2008 .SYNOPSIS...THE LONG WAVE PATTERN FEATURES A LOW SPINNING WELL E OF NC OVER THE NW ATLANTIC AND A BIG RIDGE OVER THE SERN U.S. WITH HIGHEST HEIGHTS OVER GA. UPSTREAM, WE SEE A SHORT WAVE HAS WORKED ITS WAY THROUGH THE BASE OF A TROUGH AND IS NOW LIFTING NEWD ACROSS ERN CO. ADDITIONAL ENERGY IS APPROACHING THE PAC NW COAST. SURFACE ANALYSIS SHOWS HIGH PRESSURE OVER THE SERN STATES. A COLD FRONT IS PUSHING EWD ACROSS NEW ENGLAND AND EXTENDS SWWD TO THE OHIO VALLEY. FROM THERE, THE FRONT IS CURRENTLY STATIONARY OVER THE SRN PLAINS. SKIES ARE GENERALLY CLEAR OVER THE LOCAL FORECAST AREA WITH LIGHT E WINDS STARTING TO GO CALM. && .SHORT TERM...TODAY THROUGH FRI. THE DEEP LAYER RIDGE WILL SETTLE SWD OVER THE NEXT 48 HOURS. SUBSIDENCE ASSOCIATED WITH THE UPPER RIDGE WILL RESULT IN PLENTY OF SUNSHINE WITH ABOVE NORMAL AFTERNOON TEMPS TODAY AND AGAIN ON THU. LOOK FOR UPPER 80S BOTH DAYS WITH A FEW SPOTS POSSIBLY REACHING 90. WITH THE DRY AIRMASS NOW FIRMLY IN PLACE, OVERNIGHT TEMPS WILL DROP BACK TO NEAR SEASONAL NORMS TONIGHT WITH MOST INLAND AREAS DIPPING TO THE MID 50S. COULD SEE A BIT OF FOG DEVELOPING OVER S CENTRAL GA AND ERN FL BIG BEND ZONES EARLY THU MORNING. BY THU NIGHT, THE RIDGE WILL BE S OF THE AREA OVER THE GULF OF MEXICO AS A TROUGH BEGINS DEEPENING ACROSS THE ERN U.S. THE TROUGH WILL CONTINUE TO SHARPEN ON FRI AS ENERGY CURRENTLY OFF THE PAC NW COAST DIVES INTO THE BASE OF THE TROUGH. THIS AMPLIFYING PATTERN WILL HELP PUSH THE FRONT INTO DIXIE. THE NAM IS SLOWER TO BRING THIS FRONT SEWD THAN THE PREFERRED GFS. WE ACCEPTED THE MAV POPS FOR THIS FRONTAL PASSAGE WHICH RANGE FROM CHANCE ACROSS THE NWRN HALF OF THE FORECAST AREA TO SILENT 10S OVER THE SERN FL BIG BEND. SLIGHT CHANCE POPS WILL BE USED FOR VLD TO TLH TO PFN. THIS FORECAST INDICATES A SLIGHT DOWNWARD ADJUSTMENT IN POPS FOR OUR SERN ZONES. .LONG TERM...FRI NIGHT THROUGH WED. LONG TERM PORTION OF THE FORECAST WILL BE GENERALLY QUIET. BOTH THE 15/00Z GFS AND THE 14/12Z EURO ARE IN GOOD AGREEMENT WITH THE OVERALL EVOLUTION OF THE SYNOPTIC PATTERN ACROSS THE CONUS. THE UPPER TROF THAT WILL BE RESPONSIBLE FOR PUSHING A COLD FRONT THROUGH OUR REGION BY SATURDAY MORNING WILL MOVE EAST OUT INTO THE ATLANTIC WITH SURFACE HIGH PRESSURE BUILDING SOUTHWARD FROM THE NORTHEAST THROUGH THE WEEKEND. BY LATE MONDAY...THE UPPER AIR PATTERN IS FORECAST TO BECOME HIGHLY AMPLIFIED WITH A TROF ON THE WEST AND EAST COAST WITH A LARGE MID LEVEL RIDGE BUILDING OVER THE PLAINS. UP UNTIL THIS POINT...THE MID LEVEL PATTERN HAD BEEN QUITE PROGRESSIVE. HOWEVER...AS THIS MID LEVEL RIDGE FURTHER AMPLIFIES INTO WEDNESDAY...THE PATTERN IS PREDICTED THE STALL...TO A GREATER DEGREE IN THE EURO...WITH THE HIGH AMPLITUDE RIDGE CENTERED OVER THE MISSISSIPPI RIVER VALLEY WITH AN OMEGA TYPE BLOCKING PATTERN SETTING UP FOR THE REMAINDER OF THE LONG TERM FORECAST. IF THE LATEST GFS IS CORRECT...THE BLOCKING PATTERN WILL BREAK DOWN QUICKER WITH A POTENT SYSTEM MOVING INTO THE MISSISSIPPI RIVER VALLEY BY THE FIRST PART OF THE WEEKEND. IN THE WAKE OF THE COLD FRONT ON SATURDAY...TEMPERATURES WILL RETURN TO NORMAL VALUES FOR MID OCTOBER WITH HIGHS IN THE UPPER 70S AND LOWS IN THE MID TO UPPER 50S. IT APPEARS AS THOUGH THE MID AND UPPER 80S OF LAST WEEKEND AND THE EARLY PART OF THIS WEEK WILL BE A DISTANT MEMORY BY NEXT WEEK. && .MARINE...TODAY THROUGH SUN. WINDS ARE RUNNING IN THE EXERCISE CAUTION RANGE AS OF 06Z AND WE PLAN TO LEAVE THE HEADLINE IN FOR ONE MORE PACKAGE. WINDS AND SEAS WILL CONTINUE TO DIMINISH THROUGH THE DAY TODAY AS THE SURFACE HIGH DROPS SWD. THERE WILL STILL BE ENOUGH ELY FLOW TONIGHT FOR SOME NOCTURNAL SURGE, BUT SPEEDS WILL REMAIN AOB 15 KT. AFTER THAT LOOK FOR LIGHT WINDS AND LOW SEAS FOR THU AND FRI. WINDS WILL SWITCH TO OFFSHORE BEHIND A COLD FRONT FRI NIGHT AND THEN INCREASE OUT OF THE E ONCE AGAIN FOR SAT NIGHT INTO SUN. EXERCISE CAUTION CONDITIONS ARE ANTICIPATED DURING THAT TIME. && .AVIATION...CLEAR SKIES ACROSS THE REGION AS OF 05Z WILL PERSIST THROUGHOUT MUCH OF THE TAF CYCLE. VFR CONDITIONS ARE EXPECTED THROUGHOUT THE TAF CYCLE...EXCEPT JUST PRIOR TO DAYBREAK WHEN SHALLOW GROUND FOG MAY FORM AND DROP VSBYS INTO THE MVFR RANGE AT ALL TERMINALS EXCEPT PFN. AFTER 14Z...ALL SITES VFR WITH SKIES GENERALLY SKC TO FEW050 BY 21Z. HIGH PRESSURE BUILDS OVERHEAD LATE WEDNESDAY NIGHT WITH WINDS GOING CALM AND SKIES STAYING CLEAR. && .FIRE WEATHER...DRIER AIRMASS WILL CONTINUE TO REMAIN IN PLACE ACROSS THE REGION THROUGHOUT THE NEXT COUPLE OF DAYS. HOWEVER...RELATIVELY HUMIDITY VALUES WILL ONLY DROP TO OR JUST BELOW CRITICAL LEVELS FOR A COUPLE OF HOURS BOTH WEDNESDAY AND THURSDAY AFTERNOONS. TRANSPORT WINDS AROUND 14 MPH TODAY WILL CREATE HIGH ENOUGH DISPERSIONS TO REQUIRE A RED FLAG WARNING FOR THE INTERSTATE 10 COUNTIES FROM LEON WESTWARD TO WALTON. LIGHTER WINDS ON THURSDAY WILL PRECLUDE THE NEED FOR A WATCH AT THIS TIME...HOWEVER LATER SHIFTS WILL NEED TO CHECK FUTURE MODEL RUNS IN THE EVENT LONGER DURATIONS OF LOW RELATIVE HUMIDITY ARE INDICATED. && .PRELIMINARY POINT TEMPS/POPS... TALLAHASSEE 87 54 89 55 86 / 00 00 00 05 20 PANAMA CITY 86 65 89 64 85 / 00 00 00 05 20 DOTHAN 89 57 88 59 81 / 00 00 00 10 40 ALBANY 88 55 87 59 84 / 00 00 00 05 30 VALDOSTA 87 56 88 58 85 / 00 00 00 05 20 CROSS CITY 89 56 90 56 89 / 00 00 00 05 10 && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...RED FLAG WARNING 18-22Z FOR THE FOLLOWING ZONES: GADSDEN...HOLMES...INLAND WALTON...JACKSON...LEON. GM...NONE. && $$ AVIATION/FIRE WX/LONG TERM...GODSEY REST OF DISCUSSION...WOOL