044
FXUS62 KJAX 201228
AFDJAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
828 AM EDT SUN SEP 20 2026
KEY MESSAGES
FOR THE LATEST NE FL AND SE GA DAILY KEY MESSAGES PLEASE VISIT:
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- SCATTERED TO NUMEROUS MAINLY AFTERNOON & EVENING TSTORMS
THROUGH WED. ISOLATED STRONG STORMS POSSIBLE FOR LOCATIONS
WEST OF I-95 THIS AFTERNOON THROUGH. WIND GUSTS OF 35-45 MPH,
FREQUENT LIGHTNING STRIKES, AND SMALL HAIL POSSIBLE. LOCALLY
HEAVY RAINFALL POSSIBLE ON MONDAY AFTERNOON AND EVENING
- MODERATE RIP CURRENT RISK CONTINUES AT ALL AREA BEACHES
THROUGH MIDWEEK
- STRENGTHENING ONSHORE WINDS WILL INCREASE MARINE HAZARDS FROM
LATE WEDNESDAY THROUGH NEXT WEEKEND. HIGH RISK FOR RIP
CURRENTS AND ROUGH SURF EXPECTED AT AREA BEACHES. MINOR
COASTAL FLOODING POSSIBLE AROUND TIMES OF HIGH TIDE LATE THIS
WEEK
NEAR TERM /THROUGH TONIGHT/
MAIN HIGHLIGHTS THROUGH TONIGHT:
- SCATTERED TO NUMEROUS MAINLY AFTERNOON AND EARLY EVENING
THUNDERSTORMS TODAY.
- ISOLATED STRONG STORMS POSSIBLE AT INLAND LOCATIONS LATE THIS
AFTERNOON AND EARLY THIS EVENING.
- MODERATE RIP CURRENT RISK CONTINUES AT ALL AREA BEACHES.
EARLY MORNING SURFACE ANALYSIS DEPICTS A TROUGH OVER THE SPINE OF
THE FL PENINSULA, WITH A WEAK PRESSURE PATTERN OTHERWISE PREVAILING
ACROSS OUR REGION. MEANWHILE, HIGH PRESSURE (1024 MILLIBARS)
POSITIONED OVER COASTAL NEW ENGLAND HAS PUSHED A "BACKDOOR" FRONTAL
BOUNDARY SOUTHWARD ACROSS THE SOUTHERN APPALACHIANS, WITH THIS
BOUNDARY EXTENDING EASTWARD TO THE COASTAL CAROLINA REGION.
ALOFT...A TROPICAL UPPER TROPOSPHERIC TROUGH (TUTT) WAS NEARLY
STATIONARY AS IT SPINS JUST WEST OF THE TAMPA BAY REGION. OTHERWISE,
"HEAT WAVE" RIDGING OVER EASTERN TEXAS, THE OZARKS, AND THE LOWER
MISSISSIPPI VALLEY WAS IN THE PROCESS OF WEAKENING AS TROUGHING OVER
THE ROCKIES AND THE SOUTHERN PLAINS PROGRESSES SLOWLY EASTWARD.
LATEST GOES-EAST DERIVED TOTAL PRECIPITABLE WATER IMAGERY INDICATES
THAT PWATS REMAIN ABOVE LATE SEPTEMBER CLIMATOLOGY ACROSS OUR AREA,
WITH VALUES IN THE 1.8 - 2 INCH RANGE. ISOLATED TO WIDELY SCATTERED
SHOWERS WERE WEAKENING AS THEY PROGRESS SLOWLY WEST-SOUTHWESTWARD
ACROSS THE OKEFENOKEE SWAMP AND THE SUWANNEE VALLEY, WHILE
CONVECTION ASSOCIATED WITH THE AFOREMENTIONED TUTT FEATURE WAS
BLOSSOMING OVER THE OFFSHORE WATERS NORTH OF ST. AUGUSTINE. PATCHES
OF MOSTLY MID AND HIGH ALTITUDE CLOUD COVER WERE DRIFTING ACROSS OUR
SKIES, WITH TEMPERATURES AND DEWPOINTS IN THE 70S AREA-WIDE AS OF
08Z.
A RATHER STAGNANT WEATHER PATTERN IS EXPECTED ACROSS OUR AREA TODAY
AS THE TUTT FEATURE AND ITS ACCOMPANYING SURFACE TROUGH REMAIN
STATIONARY NEAR TAMPA BAY AND OVER THE FL PENINSULA, RESPECTIVELY.
LOW LEVEL EAST-NORTHEASTERLY FLOW WILL PREVAIL, WITH A MOIST AND
UNSTABLE ATMOSPHERE PROMOTING SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS THAT WILL PROGRESS WESTWARD. SCATTERED CONVECTION OVER
THE ATLANTIC WATERS EARLY THIS MORNING SHOULD EDGE TOWARDS COASTAL
LOCATIONS AS THE MORNING PROGRESSES, WITH ACTIVITY THEN INCREASING
IN COVERAGE AND INTENSITY THIS AFTERNOON AS THE ATLANTIC SEA BREEZE
PUSHES SHOWERS AND THUNDERSTORMS WEST OF THE I-95 CORRIDOR BY THE
MID TO LATE AFTERNOON HOURS. RELATIVELY COOL TEMPERATURES ALOFT,
SUPPLIED BY THE TUTT FEATURE, SHOULD ALLOW FOR A FEW STORMS TO
"PULSE" AND BECOME STRONG TO THE WEST OF THE I-95 CORRIDOR LATER
THIS AFTERNOON AND POSSIBLY CONTINUING IN THE SUWANNEE VALLEY AND
PORTIONS OF INTERIOR SOUTHEAST GA THIS EVENING, WITH STRONGER STORMS
BEING CAPABLE OF PRODUCING DOWNBURST WINDS OF 35-45 MPH, FREQUENT
LIGHTING STRIKES, HEAVY DOWNPOURS, AND POSSIBLY SMALL HAIL AS WELL.
BREAKS IN THE MID AND HIGH ALTITUDE CLOUD COVER THIS MORNING SHOULD
ALLOW HIGHS TO CLIMB TO THE UPPER 80S AND LOWER 90S, WITH HEAT INDEX
VALUES PEAKING AROUND 100 BEFORE CONVECTIVE COVERAGE AND CLOUD COVER
INCREASES LATER THIS AFTERNOON.
CONVECTION MAY LINGER EARLY THIS EVENING ACROSS THE SUWANNEE VALLEY
AND INLAND SOUTHEAST GA, WITH THIS ACTIVITY THEN SHIFTING WEST OF
THE ALAPAHA AND SUWANNEE RIVERS BEFORE MIDNIGHT. CONVERGENT LOW
LEVEL EAST-NORTHEASTERLY FLOW AND PLENTY OF AVAILABLE MOISTURE
SHOULD ALLOW FOR WIDELY SCATTERED SHOWERS AND POSSIBLY A FEW
EMBEDDED THUNDERSTORMS TO DEVELOP AND BLOSSOM OVER THE ATLANTIC
WATERS AGAIN OVERNIGHT, AND THIS ACTIVITY SHOULD APPROACH COASTAL
SOUTHEAST GA AND PORTIONS OF COASTAL NORTHEAST FL BEFORE SUNRISE ON
MONDAY. PATCHY FOG FORMATION WILL ALSO BE POSSIBLE AT INLAND
LOCATIONS TOWARDS SUNRISE, MAINLY WEST OF THE U.S. HIGHWAY 301
CORRIDOR. LOWS WILL GENERALLY FALL TO THE 70-75 DEGREE RANGE ACROSS
OUR AREA LATER TONIGHT.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/
MAIN HIGHLIGHTS THIS PERIOD: (MONDAY THROUGH TUESDAY NIGHT)
- SCATTERED TO NUMEROUS MAINLY AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS EXPECTED.
- A FEW STRONG STORMS WITH LOCALLY HEAVY RAINFALL ARE POSSIBLE,
ESPECIALLY ON MONDAY.
THE TUTT FEATURE AND ITS ACCOMPANYING SURFACE TROUGH WILL MOVE
SLOWLY NORTHEASTWARD ACROSS OUR AREA ON MONDAY, WITH WEAK
CYCLOGENESIS THEN POSSIBLE OFF THE SOUTHEASTERN U.S. SEABOARD ON
TUESDAY AS THESE FEATURES LIFT SLOWLY AWAY FROM OUR REGION. LOW-
LEVEL ONSHORE WINDS WILL CONTINUE, AND CONVECTION MAY GET AN EARLY
START ON MONDAY AT COASTAL LOCATIONS AND ALONG THE I-95 CORRIDOR AS
TEMPERATURES ALOFT CONTINUE TO GRADUALLY COOL IN ASSOCIATION WITH
THE TUTT MOVING OVERHEAD. ACTIVITY WILL THEN PROGRESS SLOWLY INLAND
AS THE DAY CONTINUES, WITH A FEW STRONG STORMS POSSIBLE FURTHER
INLAND. SLOW STORM MOTION COULD ALSO RESULT IN LOCALLY HEAVY
RAINFALL AMOUNTS. HIGHS ON MONDAY SHOULD AGAIN CLIMB TO THE UPPER
80S AND LOWER 90S, WITH PLENTY OF HUMIDITY ALLOWING HEAT INDICES TO
AGAIN PEAK AROUND OR JUST ABOVE 100 AT INLAND LOCATIONS.
CONVECTION SHOULD CONTINUE TO SHIFT WEST OF OUR AREA DURING THE
EVENING HOURS, WITH NOCTURNAL ACTIVITY FLARING OVER THE ATLANTIC
WATERS THEN EDGING TOWARDS COASTAL LOCATIONS BY EARLY TUESDAY
MORNING. LOW LEVEL FLOW WILL BECOME MORE SOUTHERLY BY TUESDAY
AFTERNOON AS THE TUTT FEATURE AND DEVELOPING SURFACE LOW PROGRESS
AWAY FROM OUR REGION, WITH PLENTY OF MOISTURE LEFT BEHIND ALLOWING
FOR SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS TO DEVELOP ALONG
INLAND MOVING SEA BREEZES ON TUESDAY AFTERNOON. TEMPERATURES ALOFT
WILL NOT BE QUITE AS COOL ON TUESDAY, BUT HIGHS REACHING THE UPPER
80S AND LOWER 90S COULD STILL PROVIDE ENOUGH INSTABILITY FOR STORMS
TO "PULSE" AS MESOSCALE BOUNDARIES COLLIDE DURING THE AFTERNOON AND
EARLY EVENING HOURS AT INLAND LOCATIONS, WHERE ISOLATED STRONG
STORMS CONTAINING BRIEFLY GUSTY WINDS, FREQUENT LIGHTNING STRIKES,
AND SLOW MOVING, LOCALLY HEAVY DOWNPOURS WILL BE POSSIBLE. ACTIVITY
WILL DISSIPATE BY THE MID TO LATE EVENING HOURS AT INLAND LOCATIONS,
WITH LATE NIGHT CONVECTION AGAIN POSSIBLY IMPACTING COASTAL
LOCATIONS BEFORE SUNRISE ON WEDNESDAY. LOWS WILL REMAIN MOSTLY IN
THE LOW AND MID 70S ACROSS OUR AREA.
LONG TERM /WEDNESDAY THROUGH SATURDAY/
MAIN HIGHLIGHTS THIS PERIOD: (WEDNESDAY THROUGH SUNDAY):
- SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS CONTINUE ON
WEDNESDAY.
- STRENGTHENING NORTHEASTERLY WINDS WILL BRING INCREASING MARINE
HAZARDS TO COASTAL LOCATIONS ON THURSDAY AND FRIDAY.
- COOLER TEMPERATURES ARE FORECAST LATER THIS WEEK AND INTO NEXT
WEEKEND AREA-WIDE.
- MINOR COASTAL FLOODING POSSIBLE AROUND TIMES OF HIGH TIDE LATE
THIS WEEK AND NEXT WEEKEND.
TROUGHING WILL DIG OVER THE EASTERN HALF OF THE NATION DURING THE
LONG TERM PERIOD, WITH STRONG SURFACE HIGH PRESSURE BUILDING OVER
SOUTHEASTERN CANADA AND NEW ENGLAND WEDGING DOWN THE SOUTHEASTERN
SEABOARD ON WEDNESDAY AFTERNOON AND EVENING. THIS WEATHER PATTERN
WILL DRIVE A COLD FRONT SOUTHWARD INTO OUR REGION, WITH DEEP
MOISTURE POOLING DOWNSTREAM OF THIS FRONT ACROSS OUR AREA. SCATTERED
TO NUMEROUS SHOWERS AND THUNDERSTORMS SHOULD CONTINUE ACROSS OUR
AREA ON WEDNESDAY, ESPECIALLY AS THE FRONT APPROACHES DURING THE
AFTERNOON AND EVENING HOURS. A FEW STRONG STORMS AND LOCALLY HEAVY
RAINFALL WILL CONTINUE TO BE POSSIBLE, WITH ACTIVITY LIKELY
CONCENTRATING ACROSS INLAND PORTIONS OF NORTHEAST AND NORTH CENTRAL
FL DURING THE AFTERNOON AND EVENING HOURS AS OUR LOCAL PRESSURE
GRADIENT TIGHTENS, CREATING BREEZY NORTHEASTERLY WINDS ALONG THE I-
95 CORRIDOR BY THE LATE AFTERNOON HOURS. HIGHS WILL RANGE FROM THE
MID 80S AT COASTAL LOCATIONS TO AROUND 90 AT INLAND LOCATIONS.
SHOWERS AND THUNDERSTORMS MAY CONTINUE ON WEDNESDAY NIGHT ACROSS
NORTHEAST AND NORTH CENTRAL FL AS THE FRONTAL BOUNDARY SHIFTS
SOUTHWARD THROUGH OUR AREA, WITH BREEZY NORTHEASTERLY WINDS
POTENTIALLY PRODUCING WAVES OF COASTAL SHOWERS AND POSSIBLY A FEW
EMBEDDED THUNDERSTORMS THROUGHOUT THE NIGHT ALONG THE I-95 CORRIDOR.
COOL AIR ADVECTION IN THE WAKE OF THE FRONTAL PASSAGE COULD DROP
LOWS TO THE UPPER 60S DESPITE AN ABUNDANCE OF CLOUD COVER ACROSS
SOUTHEAST GA ON WEDNESDAY NIGHT, WITH LOW TO MID 70S PERSISTING
ELSEWHERE.
STRONG HIGH PRESSURE WILL PERSIST OVER NEW ENGLAND LATE THIS WEEK,
WITH LOW PRESSURE INITIALLY OFFSHORE OF THE SOUTHEASTERN STATES THEN
POTENTIALLY STRENGTHENING OFF THE MID-ATLANTIC COAST. THIS WEATHER
PATTERN WILL KEEP BREEZY NORTHEASTERLY WINDS IN PLACE ON THURSDAY
ALONG THE I-95 CORRIDOR, AND THESE WINDS MAY SHIFT TO NORTHERLY BY
FRIDAY AND SATURDAY, POTENTIALLY USHERING IN A COOLER AND DRIER AIR
MASS INTO OUR REGION. GUSTY ONSHORE WINDS ON THURSDAY SHOULD STILL
PROVIDE COASTAL SHOWERS FOR COASTAL NORTHEAST FL, BUT RAIN CHANCES
COULD THEN DECREASE BY FRIDAY AND SATURDAY DEPENDING ON HOW THE
COASTAL STORM EVOLVES OFF THE MID-ATLANTIC COAST. HIGHS SHOULD
REMAIN IN THE LOW AND MID 80S FROM THURSDAY ONWARD AREA-WIDE, AND
LOWS COULD FALL INTO THE LOWER 60S FOR INLAND SOUTHEAST GA AND THE
MID TO UPPER 60S ELSEWHERE INLAND BY LATE THIS WEEK AND INTO NEXT
WEEKEND. COASTAL LOWS MAY FALL TO AROUND 70 AS WINDS BECOME MORE
NORTHERLY AND COOL AIR ADVECTION CONTINUES LATER THIS WEEK AND INTO
NEXT WEEKEND.
ASTRONOMICAL TIDES WILL BE ON THE RISE LATER THIS WEEK DUE TO THE
UPCOMING FULL "HARVEST" MOON, AND MINOR COASTAL FLOODING DURING
TIMES OF HIGH TIDE ALONG THE ATLANTIC COAST AND WITHIN THE ST. JOHNS
RIVER BASIN WILL BE A POSSIBILITY LATER THIS WEEK AND INTO NEXT
WEEKEND, ALL DEPENDING ON THE STRENGTH AND POSITIONING OF COASTAL
LOW PRESSURE TO OUR NORTH AND THE TRAJECTORY OF SURFACE WINDS.
AVIATION /12Z SUNDAY THROUGH 12Z MONDAY/
MORE ACTIVE CONVECTIVE DAY THIS AFTERNOON. THOUGH THERE IS POTENTIAL
FOR ISOLATED COASTAL SHOWERS THROUGH 16Z, MOST SHOWER AND
THUNDERSTORM DEVELOPMENT WILL FOCUS ALONG THE INLAND MOVING ATLANTIC
SEA BREEZE. HIGHEST CONFIDENCE FOR DOWNPOURS AND THUNDERSTORM
INFLUENCES WILL BE AT INLAND AIRFIELDS 40-70% THIS AFTERNOON AND
EARLY EVENING (18-23Z). DOWNPOURS WILL RESTRICT VISIBILITY AT TIMES
AT KJAX/KVQQ/KGNV WITH VISIBILITY BRIEFLY FALLING TO IFR OR LOWER
WITH +TSRA. LIGHT NORTHWEST TO NORTHERLY SURFACE WINDS WILL SHIFT TO
NORTHEASTERLY AT 5-10 KNOTS BY 16Z AND THEN EASTERLY AROUND 10 KNOTS
BY 20Z. SURFACE WINDS WILL THEN SHIFT TO SOUTHEASTERLY WITH
DIMINISHING SPEEDS AFTER 01Z THIS EVENING. AS WINDS TREND CALM,
THERE WILL BE POTENTIAL FOR PATCHY LOW STRATUS AND LIGHT FOG AT
INLAND AIRFIELDS AFTER 08Z.
MARINE
SURFACE TROUGHING AND A DISTURBANCE ALOFT LOCATED JUST WEST OF TAMPA
BAY WILL REMAIN NEARLY STATIONARY THROUGH TONIGHT BEFORE LIFTING
SLOWLY NORTH-NORTHEASTWARD ACROSS OUR LOCAL WATERS BY MONDAY NIGHT
AND TUESDAY. SCATTERED SHOWERS AND THUNDERSTORMS WILL REMAIN
POSSIBLE THROUGH TONIGHT, WITH COVERAGE THEN INCREASING FROM MONDAY
THROUGH AT LEAST THURSDAY. EAST-NORTHEASTERLY WINDS WILL PREVAIL
THROUGH TUESDAY, WITH SPEEDS AND SEAS REMAINING BELOW CAUTION LEVELS
OUTSIDE OF THUNDERSTORM ACTIVITY. STRONG HIGH PRESSURE BUILDING OVER
SOUTHEASTERN CANADA AND NEW ENGLAND ON TUESDAY WILL BEGIN TO WEDGE
DOWN THE SOUTHEASTERN SEABOARD ON WEDNESDAY AFTERNOON AND EVENING,
CREATING A SURGE OF NORTHEASTERLY WINDS THAT WILL LIKELY CREATE
SMALL CRAFT ADVISORY CONDITIONS ACROSS OUR LOCAL WATERS BY THURSDAY
AND FRIDAY.
RIP CURRENTS: PERSISTENT EAST-NORTHEASTERLY WINDS WILL KEEP A
LOWER-END MODERATE RISK IN PLACE THROUGH MIDWEEK AT ALL AREA
BEACHES. A SURGE OF STRENGTHENING NORTHEASTERLY WINDS AND BUILDING
BREAKER HEIGHTS WILL ARRIVE ON WEDNESDAY EVENING, AND A HIGH RISK IS
LIKELY AT ALL AREA BEACHES ON THURSDAY AND FRIDAY, POSSIBLY
CONTINUING INTO NEXT WEEKEND.
FIRE WEATHER
LOW DAYTIME DISPERSION VALUES FOR COASTAL SOUTHEAST GEORGIA AND
- PORTIONS OF COASTAL NORTHEAST FLORIDA TODAY
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP EACH DAY THROUGH THURSDAY, MAINLY DURING THE AFTERNOON AND
EVENING HOURS. ACTIVITY WILL GENERALLY PROGRESS FROM EAST TO WEST,
WITH SHOWERS AND THUNDERSTORMS CONCENTRATING ALONG THE INTERSTATE 10
CORRIDOR, THE SUWANNEE VALLEY, AND THE OKEFENOKEE SWAMP THIS
AFTERNOON THROUGH EARLY THIS EVENING. OTHERWISE, EAST-NORTHEASTERLY
SURFACE AND TRANSPORT WINDS WILL PREVAIL THROUGH TUESDAY, FOLLOWED
BY GRADUALLY STRENGTHENING NORTHEASTERLY SURFACE AND TRANSPORT WINDS
ON WEDNESDAY, WITH STRONGER SPEEDS THEN FORECAST ON THURSDAY AND
FRIDAY. LIGHTER SPEEDS TODAY WILL YIELD MARGINALLY LOW DAYTIME
DISPERSION VALUES FOR COASTAL SOUTHEAST GEORGIA AND PORTIONS OF
COASTAL NORTHEAST FLORIDA, WITH GENERALLY POOR VALUES FORECAST
ELSEWHERE, EXCEPT FAIR VALUES FOR NORTH CENTRAL FLORIDA. POOR TO
FAIR DAYTIME DISPERSION VALUES WILL CONTINUE THROUGH MIDWEEK, EXCEPT
FOR GOOD VALUES ACROSS INLAND SOUTHEAST GEORGIA ON WEDNESDAY.
FOG POTENTIAL...PATCHY FOG FORMATION IS POSSIBLE ACROSS INLAND
PORTIONS OF SOUTHEAST GEORGIA, THE SUWANNEE VALLEY AND INLAND
PORTIONS OF NORTH CENTRAL FLORIDA DURING THE PREDAWN AND EARLY
MORNING HOURS ON SUNDAY AND MONDAY.
PRELIMINARY POINT TEMPS/POPS
AMG 91 70 91 70 / 40 20 30 0
SSI 87 75 88 74 / 30 30 40 20
JAX 89 71 90 72 / 50 20 50 10
SGJ 87 75 88 74 / 30 10 40 20
GNV 89 71 91 71 / 60 30 70 10
OCF 90 71 91 72 / 50 20 70 20
JAX WATCHES/WARNINGS/ADVISORIES
FL...NONE.
GA...NONE.
MARINE...NONE.
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