417 FXUS62 KJAX 141901 AFDJAX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE JACKSONVILLE FL 256 PM EDT THU MAR 14 2013 ...FROST ADVISORY INLAND TONIGHT... ...CONTINUED DRY WITH A WARM UP THIS WEEKEND... .SHORT TERM (TONIGHT-SATURDAY NIGHT)... TONIGHT...COOL HIGH PRESSURE BUILDS IN ACROSS NORTH FL LATE TONIGHT. WITH MOSTLY CLEAR SKIES...NEAR CALM WIND...AND COOL AND DRY AIR IN PLACE...TEMPS EXPECTED TO RAPIDLY FALL OFF INTO THE LOWER TO MID 30S ACROSS MUCH OF THE INLAND AREAS. WITH GOOD RADIATIONAL COOLING AND ELEVATED DEWPOINT TEMPS STAGE SET FOR FROST ACROSS THE INLAND AREAS AND HAVE POSTED A FROST ADVISORY FROM LATE TONIGHT INTO EARLY MONDAY MORNING. FRIDAY/FRIDAY NIGHT...HIGH PRESSURE BEGINS TO WEAKEN AND MOVES ACROSS NORTH CENTRAL FL. LIGHT NW WINDS IN THE MORNING BECOME SW AND W IN THE AFTERNOON. SEA BREEZES EXPECTED AT BOTH GULF AND ATLANTIC COASTS. AIR MASS MODIFIES AND AFTER COLD START...MAX TEMPS REACH THE LOWER 70S INLAND. SEA BREEZE KEEPS THE COAST IN THE UPPER 60S. CLEAR SKIES EXPECTED FRIDAY NIGHT BUT MIN TEMPS WILL BE AROUND 10 DEGREES WARMER AND NO FROST IS EXPECTED. SATURDAY...HIGH PRESSURE SHIFTS FURTHER SOUTH ACROSS CNTL FL WHILE LOW PRESSURE TRACKS ACROSS VA AND NC. THE TIGHT GRADIENT BETWEEN THE TWO WILL PRODUCE BREEZY AND WARM SW WINDS. WITH SUNNY SKIES EXPECTED...HIGH TEMPS WILL BE WELL INTO THE 70S AT MOST LOCALES...INCLUDING THE COAST. SATURDAY NIGHT...RIDGE OF HIGH PRESSURE SHIFTS NORTH INTO THE AREA. WITH CLEAR SKIES AND LIGHT WINDS LOW TEMPS WILL FALL INTO THE MID/UPPER 40S INLAND AND AROUND 50 COAST WHICH IS BELOW NORMAL. .LONG TERM...(SUNDAY-THURSDAY)... THE ABOVE NORMAL TEMPERATURE READINGS AND DRY AIRMASS WILL CONTINUE INTO EARLY NEXT WEEK WITH HIGH PRESSURE SHIFTING EAST OF THE REGION. THE NEXT FRONTAL BOUNDARY SHOULD MOVE SOUTHEAST ACROSS REGION IN THE MONDAY NIGHT TO TUESDAY TIMEFRAME. MODELS ARE TRENDING TOWARD A WEAKENING TREND WITH THE FRONT...AS THE BETTER ENERGY SHIFTS NORTHEAST. SO...CONTINUE TO FORECAST LOW POPS FOR THIS PERIOD. HIGH PRESSURE PUSHES SOUTH BEHIND THE BOUNDARY FOR MIDWEEK. NOT MUCH OF A SOUTHERN EXTENT TO THE COOLER AIRMASS BEHIND THIS SYSTEM...SO ONLY A SLIGHT COOL DOWN EXPECTED. && .AVIATION...VFR CONTINUES. WINDS WILL AROUND 10 KT FROM THE N AND NE. WINDS WILL BE LESS THAN 10 KT BY EARLY THIS EVENING. && .MARINE...SMALL CRAFT ADVY CONTINUES FOR THE OFFSHORE WATERS DUE TO MARGINAL WIND SPEED BUT SEAS OF ABOUT 7 FT AT 41012. WINDS WILL BE WEAK TONIGHT INTO FRI AS HIGH PRES MOVES CLOSER TO THE AREA. OFFSHORE FLOW PREVAILS DURING THE WEEKEND WITH NOCTURNAL SURGES IN S-SWLY WINDS. S-SW FLOW CONTINUES MON BEFORE NEXT FRONTAL PASSAGE ON TUE. .RIP CURRENTS...ELY SWELLS LIKELY TO CONTINUE ON FRI WITH A MODERATE RISK AND CONTINUED N-S LONG-SHORE CURRENTS. && .FIRE WEATHER...HAVE GONE AHEAD AND CANCELLED THE RED FLAG FOR ST JOHNS AND FLAGLER COUNTIES WHERE RH VALUES HAVE NOT FALLEN TO 28% AND ANY DURATIONS ARE LIKELY TOO BE SHORT FOR FLAGS. RED FLAG CONTINUES FOR PUTNAM AND MARION COUNTIES REST OF THE AFTN. A FIRE WX WATCH MAY BE NEEDED ON FRI FOR SE ZONES WHERE ERC VALUES MAY BE AROUND 37. DECISION WILL BE MADE LATE TODAY WHETHER A FIRE WX WATCH IS NEEDED FOR THESE AREAS. && .PRELIMINARY POINT TEMPS/POPS... AMG 34 72 46 79 / 10 10 10 10 SSI 40 68 49 76 / 10 10 0 10 JAX 34 71 44 78 / 0 0 0 0 SGJ 38 68 49 74 / 0 0 0 0 GNV 33 72 41 77 / 0 0 0 0 OCF 34 73 40 78 / 0 0 0 0 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...FROST ADVISORY FROM 4 AM TO 9 AM EDT FRIDAY FOR ALACHUA-BAKER- BRADFORD-CLAY-COLUMBIA-DUVAL-GILCHRIST-HAMILTON-MARION- NASSAU-PUTNAM-SUWANNEE-UNION. RED FLAG WARNING UNTIL 7 PM EDT THIS EVENING FOR MARION-PUTNAM. GA...FROST ADVISORY FROM 4 AM TO 9 AM EDT FRIDAY FOR APPLING-ATKINSON- BACON-BRANTLEY-CHARLTON-CLINCH-COFFEE-ECHOLS-INLAND CAMDEN- INLAND GLYNN-JEFF DAVIS-PIERCE-WARE-WAYNE. AM...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ALTAMAHA SOUND GA TO FERNANDINA BEACH FL 20 NM TO 60 NM OFFSHORE- FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM OFFSHORE- ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM OFFSHORE. && $$ PP/ARS/KG