413
FXUS62 KJAX 171737
AFDJAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
1237 PM EST TUE DEC 17 2024
..NEW AVIATION
UPDATE
ISSUED AT 1024 AM EST TUE DEC 17 2024
FOR THE LATEST NE FL AND SE GA DAILY KEY MESSAGES PLEASE VISIT:
HTTPS://WWW.WEATHER.GOV/MEDIA/JAX/BRIEFINGS/NWS-JAX-BRIEFING.PDF
WITH LINGERING DENSE FOG OVER THE NEARSHORE ATLANTIC WATERS FROM
JAX NORTHWARD TO BRUNSWICK HAVE POSTED A MARINE DENSE FOG ADVISORY
SINCE THE CRITERIA IS ONLY 1NM OR LESS AND BRUNSWICK/ST. SIMONS
ISLAND HAVE RECENTLY DROPPED BACK TO 1/4 TO 1/2 MILE OR SO.
HAVE ALSO POSTED ANOTHER SPS (SPECIAL WEATHER STATEMENT) FOR
PATCHY DENSE SEA FOG ALONG THE ATLANTIC COASTAL COUNTIES FROM JAX
NORTHWARD TO BRUNSWICK TO ACCOUNT FOR SOME OF THIS SEA FOG
LINGERING IN THE INLAND WATERWAYS THROUGH TODAY THAT WILL LIKELY
PUSH INLAND AFTER SUNSET THIS EVENING.
NEAR TERM
ISSUED AT 311 AM EST TUE DEC 17 2024
FOR THE LATEST NE FL AND SE GA DAILY KEY MESSAGES PLEASE VISIT:
HTTPS://WWW.WEATHER.GOV/MEDIA/JAX/BRIEFINGS/NWS-JAX-BRIEFING.PDF
LINGERING COASTAL TROUGH COMBINED WITH GRADUALLY INCREASING LOW
LEVEL MOISTURE HAS PERSISTED PLENTY OF LOW CLOUDS AND AREAS OF FOG
THIS MORNING, IN ADDITION TO ISOLATED SHOWERS THAT HAVE MADE IT
ALL THE WAY INTO INLAND NORTHEAST FL EARLIER THIS MORNING. SOME
AREAS OF DENSE FOG WILL BE POSSIBLE TOWARDS SUNRISE THIS MORNING,
ESPECIALLY ACROSS NORTHEAST FL AND SOUTH AND EAST OF ABOUT
WAYCROSS. NOT ANTICIPATING A DENSE FOG ADVISORY BEING NEEDED AT
THIS TIME, HOWEVER WILL CONTINUE TO MONITOR TRENDS OVER THE NEXT
SEVERAL HOURS.
OTHERWISE, COASTAL TROUGHING WILL SHIFT FURTHER NORTHWARD UP THE
COAST IN RESPONSE TO WEAKENING HIGH PRESSURE TO OUR NORTH, AHEAD
OF A COLD FRONT THAT WILL WILL STALL NEAR NORTHERN GA LATER THIS
AFTERNOON AND EVENING. ALTHOUGH THIS FRONT WILL LOSE SOUTHWARD
PROGRESS DUE TO ZONAL FLOW IN PLACE ALOFT, A MOISTURE BOUNDARY IS
OBSERVED ALOFT AHEAD OF THE FRONT ACROSS CENTRAL AND SOUTHWESTERN
GA VIA SATELLITE IMAGERY AND SHORT RANGE GUIDANCE, WHICH WILL
INTRODUCE A LIFTING MECHANISM INTO A LARGE PORTION OF THE AREA
TODAY WHERE TEMPERATURES WILL RISE WELL INTO THE 70S TO NEAR 80 IN
SOME SPOTS AND DEW POINTS ALSO RISING WELL INTO THE 60S. COMBINED
WITH SOME ONSHORE FLOW/A WEAK SEA BREEZE DEVELOPING WITH THE
COASTAL TROUGH AND MUCAPE RISING INTO THE 500-1000J/KG RANGE OF
HIGHER THIS AFTERNOON, CERTAINLY THE POTENTIAL FOR SOME SHOWERS
AND ISOLATED THUNDERSTORMS ACROSS THE INTERIOR LATE THIS MORNING
AND THROUGH THE AFTERNOON HOURS TODAY, IN ADDITION TO THE ISOLATED
ACTIVITY OVER AREA WATERS AND NEAR THE COAST. ONE MAJOR FACTOR
THAT COULD INHIBIT DIURNAL ACTIVITY IS THE FOG AND LOW STRATUS IN
PLACE TO START THE DAY TODAY, AND HOW QUICKLY AND EFFICIENTLY
DISSIPATION OCCURS.
MOST CONVECTIVE ACTIVITY WILL WANE BY THIS EVENING, WITH THE
EXCEPTION OF SOME ISOLATED SHOWERS AND PERHAPS A THUNDERSTORM OR
TWO OVER AREA WATERS. LOW CLOUD AND/OR FOG DEVELOPMENT APPEARS
LIKELY TO SPREAD FROM THE NORTHEAST ONCE AGAIN TONIGHT GIVEN THE
MILD LOWS MOSTLY IN THE 60S AND A VERY LIGHT FLOW.
SHORT TERM
(WEDNESDAY THROUGH THURSDAY NIGHT)
ISSUED AT 311 AM EST TUE DEC 17 2024
WED & WED NIGHT...THIS PERIOD WILL BE THE BEST CHANCE OF RAINFALL
OVER THE UPCOMING WEEK AS A WARM FRONT LIFTS NORTH ACROSS THE AREA
WED INTO WED EVENING AHEAD OF AN APPROACHING COLD FRONT. SURFACE
BASED INSTABILITY AND THE BEST LOW LEVEL CONVERGENCE WILL FOCUS
ALONG THE LOCAL ATLANTIC COAST MIDDAY WED, THEN SHIFT FARTHER
INLAND INTO WED AFTERNOON & EVENING AS THE WARM FRONT LIFTS SLOWLY
NORTHWARD UNDER SW FLOW AHEAD OF THE PARENT 500 MB TROUGH, WITH
THE STRONGEST DEEP LAYER LIFT WELL NORTH OF THE REGION. THE BEST
MOISTURE AND INSTABILITY WILL PHASE WED AFTERNOON & EVENING ACROSS
THE LOCAL AREA WHILE THE BETTER UPPER LEVEL LIFT LAGS INTO WED
EVENING, SO THE PHASING OF SEVERE STORM INGREDIENTS IS NOT
EXPECTED WITH THIS SYSTEM. HOWEVER, STEEPER THAN CLIMO 700-500 MB
LAPSE RATES OF 6.3 TO 6.7 C/KM AND BULK SHEAR OF 25-35 KTS WITH
500 MB TEMPS -12 TO -15 DEGC (NEAR TO BELOW CLIMO) COULD PRODUCE
SOME HAIL IN STORMS THAT DEVELOP. THE HIGHER STORM TOTAL RAINFALL
AMOUNTS ARE EXPECTED TO FOCUS NEAR THE ATLANTIC COAST WHERE LOW
LEVEL CONVERGENCE WILL BE MAXIMIZED NEAR THE LIFTING WARM FRONT
AND ACROSS NE FL WHERE BETTER INSTABILITY WILL BE LOCATED.
PRECIPITATION WILL DECREASE IN COVERAGE AFTER MIDNIGHT WED NIGHT
TRAILING THE SURFACE COLD FRONT PASSAGE, BUT ALOFT SW FLOW WILL
CONTINUE, WITH THE COLDER POST-FRONTAL AIRMASS LAGGING THE SURFACE
FRONT PASSAGE. ABOVE NORMAL HIGH TEMPERATURES WED WILL RISE INTO
THE MID/UPPER 70S ALTHOUGH COASTAL LOCATIONS NEAR AND NORTH OF THE
LIFTING WARM FRONT COULD HAVE LINGERING LOW STRATUS THROUGH MIDDAY
WHICH WOULD BRING COOLER HIGHS NEAR 70. TRAILING THE FRONTAL
PASSAGE WED NIGHT, MILD LOWS WILL RANGE IN THE 50S WITH A BRIEF
PERIOD OF TRANSIENT FOG AND LOW STATUS CLOUDS NEAR THE FRONT
ACROSS NE FL SOUTH OF THE I-10 CORRIDOR THROUGH DAYBREAK WEDNESDAY
MORNING.
THU & THU NIGHT...DRIER AND COOLER WITH LINGERING LOW LEVEL CLOUDS
THURSDAY UNDER LOW LEVEL NNW WINDS. HOWEVER, JUST ABOVE THE
SURFACE, WSW MID AND UPPER LEVEL FLOW WILL CONTINUE A RELATIVELY
'WARM' AIRMASS WITH HIGHS IN THE 70S FOR MOST LOCATIONS AND A LOW
CHANCE (10-20%) OF A PASSING SHOWER WITH THE APPROACH OF A
MID/UPPER LEVEL SHORT WAVE TROUGH INTO THU EVENING. THU NIGHT, A
COOLER AND DRIER WNW FLOW. TEMPERATURES WILL COOL THU NIGHT INTO
THE MID/UPPER 40S ACROSS SE GA TO THE LOWER 50S ACROSS NE FL, BUT
NOT A DRAMATIC COOL DOWN GIVEN VERY SHALLOW COLD AIR ADVECTION.
LONG TERM
(FRIDAY THROUGH MONDAY)
ISSUED AT 311 AM EST TUE DEC 17 2024
DRY WEATHER WITH A COOLING TREND BEGINS FRIDAY TRAILING THE THU
EVENING SHORT WAVE TROUGH PASSAGE WITH HIGH TEMPERATURES RANGING
IN THE 60S FOR MOST AREAS TO NEAR 70 ACROSS NORTH-CENTRAL FL. FRI
NIGHT, A REINFORCING DRY COLD FRONT MOVES OFFSHORE OF THE SE
ATLANTIC COAST AS A STRONGER LONG WAVE TROUGH PRESSES DOWNSTREAM
WHICH WILL ADVECT A DEEP LAYER OF COLDER, DRIER WNW FLOW ACROSS
THE REGION. THIS REGIME WILL USHER IN A MUCH COLDER AIRMASS FOR
THE WEEKEND, WITH LOWS FALLING INTO THE MID 30S TO LOW 40S BY
DAYBREAK SATURDAY MORNING AND JUST LIGHT ENOUGH OF A PRESSURE
GRADIENT FOR SOME PATCHY INLAND FROST TO FORM IN SHELTERED AREAS.
SAT AND SUN, HIGH TEMPERATURES ARE EXPECTED TO RANGE BELOW NORMAL
IN THE 50S TO LOW 60S WITH INLAND LIGHT FREEZES FOR SE GA AND
PORTIONS OF THE SUWANNEE RIVER VALLEY AND FROST FARTHER EAST
TOWARD THE ST. JOHNS RIVER BASIN AS SURFACE HIGH PRESSURE BUILDS
NORTH THEN NORTHEAST OF THE REGION. BY MON MORNING, NNE FLOW
BEGINS TO DEVELOP AS THE SURFACE RIDGE BUILDS OFFSHORE OF THE NEW
ENGLAND COAST WITH ANOTHER INVERTED COASTAL TROUGH AXIS FORMING
OVER THE LOCAL WATERS. THIS WILL MODERATE TEMPERATURES ACROSS
COASTAL SE GA AND MUCH OF NE FL, WHILE A RIDGE AXIS WEDGING DOWN
THE LEE SIDE OF THE APPALACHIANS HOLDS ONTO ANOTHER NIGHT OF
CHILLY TEMPERATURES AND FROST POTENTIAL MON NIGHT/TUE MORNING FOR
INLAND SE GA. THE INVERTED COASTAL TROUGH WILL INCREASE LOCAL
ONSHORE FLOW LATE MON INTO TUE.
AVIATION
(18Z TAFS)
ISSUED AT 1227 PM EST TUE DEC 17 2024
VFR CONDS HAVE DEVELOPED AT GNV/SGJ, WHILE IT WILL TAKE UNTIL
19-20Z AT CRG/JAX/VQQ TO SCATTER OUT THE LOW STRATUS. MEANWHILE
SSI IS STILL LOCKED DOWN WITH LOW STRATUS AT IFR LEVELS AND WILL
RETURN DOWN TO LIFR IN SEA FOG BY SUNSET (23Z) AND WILL CONTINUE
THROUGH MOST OF THE UPCOMING FORECAST PERIOD. FURTHER SOUTH ACROSS
THE NE FL TERMINALS THE VFR CONDS WILL NOT LAST MUCH PAST SUNSET
AS ADVECTIVE SEA FOG EVENT APPEARS LIKELY WITH LIFR CONDS
DEVELOPING IN THE 02-04Z TIME FRAME AT CRG/SGJ/JAX/VQQ AND
REACHING INLAND TO THE GNV TERMINAL IN THE 04-06Z TIME FRAME.
THESE LIFR CONDS ARE EXPECTED TO REMAIN UNTIL AT LEAST 15Z DUE TO
THE LOW DECEMBER SUN ANGLE NOT PROVIDING ANY IMPROVEMENT RIGHT AT
THE END OF THE TAF PERIOD IN THE 15-18Z TIME FRAME WHICH CAN LIKELY
BE TIMED OUT MORE CLOSELY IN LATER TAF PACKAGES.
MARINE
ISSUED AT 311 AM EST TUE DEC 17 2024
AREAS OF FOG, DENSE AT TIMES, WILL LIKELY PERSIST OVER THE NEAR
SHORE WATERS THROUGH TONIGHT. MEANWHILE, STRONG HIGH PRESSURE
CENTERED OVER THE CANADIAN MARITIME REGION WILL WEAKEN THROUGH TONIGHT.
A PERSISTENT COASTAL TROUGH SITUATED OVER OUR NEAR SHORE WATERS
WILL CONTINUE TO GENERATE SCATTERED SHOWERS AND AN ISOLATED
THUNDERSTORM THROUGH TUESDAY NIGHT. THE TROUGH WILL GET STRONGER
TUESDAY NIGHT AND WEDNESDAY AS LOW PRESSURE DEVELOPS ALONG A COLD
FRONT OVER THE TENNESSEE AND OHIO VALLEYS. SHOWERS AND A FEW
THUNDERSTORMS WILL INCREASE IN COVERAGE OVER OUR LOCAL WATERS ON
WEDNESDAY AND WEDNESDAY NIGHT WELL AHEAD OF THIS APPROACHING COLD
FRONT. THIS FRONT WILL THEN CROSS OUR LOCAL WATERS EARLY ON
THURSDAY, WITH WINDS SHIFTING TO THE NORTHWEST IN THE WAKE OF THIS
FRONT LATE THIS WEEK.
RIP CURRENTS: RIP CURRENT RISK REMAINS HIGH FOR ALL AREA BEACHES
TODAY DUE TO LINGERING EFFECTS OF RECENT ONSHORE FLOW. THE RISK
DROPS TO MODERATE WEDNESDAY.
PRELIMINARY POINT TEMPS/POPS
AMG 78 59 76 55 / 20 20 30 40
SSI 69 60 70 58 / 20 20 30 40
JAX 76 60 77 58 / 20 20 40 50
SGJ 75 63 76 60 / 20 20 40 40
GNV 80 62 80 59 / 20 20 40 40
OCF 82 63 81 61 / 30 20 40 40
JAX WATCHES/WARNINGS/ADVISORIES
FL...HIGH RIP CURRENT RISK UNTIL 7 PM EST THIS EVENING FOR FLZ124-125-
133-138.
GA...HIGH RIP CURRENT RISK UNTIL 7 PM EST THIS EVENING FOR GAZ154-166.
AM...DENSE FOG ADVISORY UNTIL 10 AM EST WEDNESDAY FOR AMZ450-452.
SMALL CRAFT ADVISORY UNTIL 1 AM EST WEDNESDAY FOR AMZ470.
SMALL CRAFT ADVISORY UNTIL 5 AM EST WEDNESDAY FOR AMZ472-474.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page