000 FXUS62 KMLB 231932 AFDMLB AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MELBOURNE FL 230 PM EST MON NOV 23 2009 .DISCUSSION... ...INCREASING RAIN CHANCES THROUGH MID WEEK THEN TURNING DRIER AND MUCH COOLER FROM THANKSGIVING NIGHT INTO THIS WEEKEND... CURRENT...SHALLOW COOL FRONT BCMG INCRSGLY DIFFUSE AND APPEARS TO BE COMING TO A FULL STOP A BIT NORTH OF LAKE OKEE ATTM. CLOUD DECK HAS TRANSFORMED MORE TO DIURNAL CU/SC TOPPED BY TUFTS OF JET CI WHICH IS STREAMING IN FROM THE SW. CURRENT TEMPS L-M70S NORTH...U70S CTRL... AND L80S SOUTH. OVERNIGHT/TUE...UPR JETSTRK OVHD DEPARTS TO THE NE AS A SHORT WAVE TROUGH EMBDEDDED IN THE NOW-POTENT SRN STREAM LIFTS NEWD FROM OLD MEX INTO THE GOMEX. STALLED FRONTAL BDRY OVER THE SRN CWA WILL BEGIN TO GET OVERRUN BY INCRSG SW SLOW OF LOW-MID LVL MOISTURE FROM LATE TNGT INTO TUE...LEADING TO INCRSG CLOUDS AND RAIN CHCS AREAWIDE FOR TUE. PRETTY BIG DIPARITY BTWN MET (LKLY) AND MAV (~10%) POPS TNGT... AND AS SUCH HAVE KEPT IN SMALL CHC FOR THE CTRL SOUTH...IN CLOSEST PROXIMITY TO THE FRONT. BOTH ARE ADVERTISING 60-70 POPS FOR MOST OF THE CWA FOR TUE...WHICHIS PROBABLY NOT ALL THAT FAR OFF. TO BETTER AGREE WITH ADJCT OFFICES HAVE SHAVED BACK TO HIGH END CHC (50) FOR THE ENTIRE CWA. TUE NIGHT - WED NIGHT...DEVELOPING SFC LOW OVER THE CENTRAL GULF OF MEXICO AND DEEPENING MID LEVEL TROF PROGRESSING ACROSS THE MIDWEST WILL BEGIN TO BACK FLOW IN THE LOW-MID LEVELS TUES NIGHT...LIFTING THE WEAK FRONT THAT WILL BE LINGERING OVER THE SOUTHERN HALF OF THE PENINSULA BACK TO THE NORTH. THIS WILL BRING DEEPER MOISTURE OVER CARIB TO NORTHWARD OVER THE STATE DURING THE DAY ON WEDNESDAY. BEST CHANCES FOR RAINFALL WILL BE WEDNESDAY INTO WEDNESDAY NIGHT (ACCOUNTING FOR THE REMAINING TIMING DIFFERENCES BETWEEN THE GFS AND ECMWF)...AS EMBEDDED SHORTWAVE AND VORT MAX TRANSIT ACROSS THE STATE ALONG WITH THE SFC LOW FROM THE GULF. HAVE BUMPED POPS UP TO THE LIKELY CATEGORY (60%) ACROSS THE ENTIRE REGION ON WEDNESDAY. THE PRESENCE OF THE BOUNDARY AND WEAK DISTURBANCE ALOFT...ALONG WITH THE THE JETSTREAK NOSING INTO THE STATE MAY BE ABLE TO OVERCOME WHAT MIGHT OTHERWISE BE MARGINAL INSTABILITY ON WED. A MENTION FOR SLIGHT CHANCE OF TSTMS SEEMS WARRANTED GIVEN THE SETUP. AT THE LEAST...THERE WILL LIKELY BE THE OPPORTUNITY FOR PERIODS OF MODERATE TO HEAVY RAINFALL DURING THIS TIMEFRAME. TEMPS WILL CONTINUE MILD...ESPECIALLY AT NIGHT WITH LOWS IN THE LOW/MID 60S NORTH.... MID/UPPER 60S SOUTH. THANKSGIVING...ECMWF AND GFS BOTH HAVE THE SFC LOW OFF TO THE NORTHEAST OVER THE ATLC BY EARLY THURS MORNING...WITH THE TRAILING COLD FRONT EXITING OVER THE SOUTHERN HALF OF THE CWA. STRONG PUSH OF COOLER/DRIER AIR WILL SPREAD DOWN THE PENINSULA BEHIND IT. SHOWED A N-S POP STRIATION THURS...WITH HIGHER CHANCES EARLY IN THE DAY AND ACROSS THE SOUTH. NORTHERN AREAS WILL SEE NOTABLY COOLER TEMPERATURES AND PARTLY CLOUDY SKIES BY THE AFTERNOON. MAXES ON THANKSGIVING RANGING FROM MID 70S NORTH TO AROUND 80 IN THE SOUTH. FRI-SUN (FROM PREV DISC)...DRIER AND MUCH COOLER AIR MASS BECOMES ENTRENCHED OVER THE REGION FRIDAY. MAX TEMPS WILL TOP OUT IN THE MID 60S NORTH-LOWER 70S SOUTH FRI. OVERNIGHT LOWS EXPECTED TO BE IN THE 40S OVER MOST OF THE AREA AND MAYBE A FEW UPPER 30S COOLER NORTHERN INTERIOR BY SAT MORN. THE COOL TEMPS WILL PERSIST THROUGH MUCH OF THE WEEKEND WITH SURFACE HIGH CENTER NOT MOVING OFFSHORE OVER ATLANTIC UNTIL SUNDAY NIGHT. && .AVIATION...EXPECT WDSPRD IFR/LIFR ST FOR THE NRN HALF CWA AGAIN STARTING 07Z-09Z THRU ABOUT 14Z-15Z WITH SOME MVFR TO LOCAL IFR VSBYS. && .MARINE...EXPECT LGT WINDS GNRLY OUT OF THE N/NE AOB 10KT WITH 2-4FT ENE-E SWELL CONTINUING TO SLOWLY SUBSIDE TO AOB 3FT BY TUE. WED-SAT ...WINDS WILL SHIFT TO THE S-SE LATE TUES INTO WED AS SFC LOW CENTER CROSSES OVER OR JUST TO THE SOUTH OF THE SOUTHERN WATERS. FRONTAL BOUNDARY WILL PASS THROUGH THE REGION ON THUR...WITH STRONG NWLY SURGE DEVELOPING BEHIND THE FRONT BY THURS AFTERNOON. ADVISORY CONDITIONS WILL BE LIKELY LATE THURS EVE THROUGH SATURDAY MORNING WITH NW WINDS EXPECTED AROUND 20KTS. SEAS 2-3FT NEARSHORE...3-5 FT OFFSHORE THROUGH THURS. WIND SURGE WILL QUICKLY BUILD SEAS OVER THE OFFSHORE LEGS LATE THURS INTO SAT. && .FIRE WEATHER...WIND/LOWER RH WILL LKLY RAISE FIRE WX CONCERNS BEGINNING FRI...WITH LOW RH VALUES MERITING ATTENTION AGAIN ON SAT. && .PRELIMINARY POINT TEMPS/POPS... DAB 61 75 64 75 / 10 50 50 60 MCO 63 79 64 79 / 20 50 50 60 MLB 67 79 67 80 / 20 50 50 60 VRB 67 81 67 80 / 20 50 50 60 LEE 62 77 65 77 / 10 50 50 60 SFB 63 79 65 78 / 10 50 50 60 ORL 66 79 67 79 / 20 50 50 60 FPR 67 82 67 80 / 20 50 50 60 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$ SHORT TERM/AVIATION...CRISTALDI LONG TERM....MOSES