304
FXUS62 KJAX 250039
AFDJAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
839 PM EDT THU SEP 24 2020
UPDATE
WARM AND HUMID CONDITIONS WILL CONTINUE OVERNIGHT. AREAS OF
STRATUS AND INLAND PATCHY FOG ARE EXPECTED BY MORNING. ISOLATED
SHOWERS WILL AFFECT PARTS OF INTERIOR SE GA OVERNIGHT ALONG WITH
A FEW SHOWERS POSSIBLE NEAR THE EAST COAST DUE TO SOUTHEAST WINDS
PROVIDING COASTAL CONVERGENCE. LOWS TONIGHT WILL BE IN THE LOWER
70S INLAND AND IN THE MID 70S NEAR THE COAST. AFTERNOON SHOWERS
AND THUNDERSTORMS EXPECTED FRIDAY AFTERNOON WITH A FEW STRONG TO
SEVERE STORMS POSSIBLE OVER SE GA.
PREV DISCUSSION [730 PM EDT]
NEAR TERM [THROUGH TONIGHT]
LATE MORNING SURFACE ANALYSIS DEPICTED STRENGTHENING HIGH
PRESSURE (1018 MILLIBARS) CENTERED BETWEEN CAPE HATTERAS AND
BERMUDA. MEANWHILE, THE REMNANT LOW PRESSURE CENTER (1004
MILLIBARS) THAT WAS ONCE TROPICAL STORM BETA WAS EXITING THE LOWER
MISSISSIPPI VALLEY AND WAS PROGRESSING EAST-NORTHEASTWARD TOWARDS
THE TENNESSEE VALLEY. ALOFT...DEEP-LAYERED RIDGING WAS CENTERED
OVER THE BAHAMAS. OTHERWISE, A SHORTWAVE TROUGH THAT IS WEAKENING
OVER THE OHIO VALLEY WILL BE RE-INVIGORATED BY A MORE POTENT
UPSTREAM SHORTWAVE THAT IS DIVING SOUTHEASTWARD ACROSS THE UPPER
MIDWEST. GOES-EAST DERIVED TOTAL PRECIPITABLE WATER VAPOR IMAGERY
DEPICTS A GRADUALLY MOISTENING AIR MASS OVER OUR REGION, WITH
PWATS STILL BELOW 1.5 INCHES AREA-WIDE. A RIBBON OF DEEP TROPICAL
MOISTURE IS ADVECTING NORTHWARD FROM THE GULF OF MEXICO INTO THE
FL PANHANDLE, WHERE PWATS ARE SURGING TO ABOVE 2 INCHES.
ISOLATED SHOWERS WILL BE POSSIBLE THROUGH THE AFTERNOON HOURS
TODAY ALONG THE I-95 CORRIDOR ALONG AN INLAND MOVING ATLANTIC SEA
BREEZE BOUNDARY. A FEW SHOWERS WILL ALSO BE POSSIBLE NEAR THE
ALTAMAHA RIVER AS DEEPER MOISTURE ADVECTS NORTHEASTWARD FROM THE
GULF OF MEXICO AND THE FL PANHANDLE. OTHERWISE, BREEZY ONSHORE
WINDS WILL DEVELOP AT COASTAL LOCATIONS BY NOON AS OUR LOCAL
PRESSURE GRADIENT CONTINUES TO TIGHTEN. WARM AIR ADVECTION WILL
BOOST HIGHS INTO THE UPPER 80S AT MOST INLAND LOCATIONS, WITH LOW
TO MID 80S EXPECTED AT COASTAL LOCATIONS. MUCH WARMER LOWS ARE
EXPECTED TONIGHT AS A LOW LEVEL VEERING WIND PROFILE ADVECTS DEEP
TROPICAL MOISTURE ACROSS THE REST OF OUR REGION OVERNIGHT. A FEW
SHOWERS WILL REMAIN POSSIBLE ACROSS INLAND PORTIONS OF SOUTHEAST
GA OVERNIGHT, WITH COASTAL CONVERGENCE STRENGTHENING AND
DEVELOPING A FEW SHOWERS TOWARDS SUNRISE FOR LOCATIONS ALONG
COASTAL PORTIONS OF ST. JOHNS AND FLAGLER COUNTIES. LOWS TONIGHT
WILL RANGE FROM THE LOWER 70S INLAND TO THE MID 70S AT COASTAL
LOCATIONS.
SHORT TERM [FRIDAY THROUGH SATURDAY NIGHT]
COLD FRONT TRAILING FROM THE REMNANTS OF BETA WILL MOVE THROUGH
THE AREA FRIDAY, EXITING FRIDAY NIGHT. PWATS WILL CONTINUE TO RISE
AHEAD OF THIS SYSTEM, WITH 1.8-2.2 INCHES ON TAP FOR STORMS TO
PRODUCE ISOLATED HEAVY RAINFALL. WE'RE TRANSITIONING INTO THE TIME
OF YEAR WHEN WE'RE STARTING TO GET STRONGER WINDS ALOFT AGAIN AND
WITH ABOUT 30 KTS 0-6 KM SHEAR IN PLACE FRIDAY ALONG WITH AROUND
1500 J/KG MLCAPE, WE COULD SEE A FEW STORMS PRODUCING DAMAGING
WIND GUSTS TO AROUND 30-50 MPH. ON SATURDAY, HIGH PRESSURE WILL
BUILD OVER THE SOUTHEAST IN THE WAKE OF THE FRONT, BUT WITH
SOUTHWESTERLY FLOW FROM THE GULF, WARM TEMPERATURES, AND JUST
ENOUGH MOISTURE, COULD SEE SCATTERED SHOWERS WITH EMBEDDED
THUNDERSTORMS SATURDAY AFTERNOON.
LONG TERM [SUNDAY THROUGH THURSDAY]
A PARADE OF (MOSTLY DRY) COLD FRONTS WILL CONTINUE, BRINGING
DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS SUNDAY THROUGH
TUESDAY. A MUCH DRIER, COLDER AIRMASS WILL BUILD OVER THE AREA
TUESDAY INTO TUESDAY NIGHT, HOWEVER, SO THINGS WILL DRY OUT MID-
WEEK. TEMPERATURES WILL COOL DOWN THROUGH THE WEEK, STARTING NEAR
90 ON SUNDAY AND RETURNING BACK TO THE UPPER 70S-LOW 80S BY
THURSDAY. OVERNIGHT LOWS WILL DROP THROUGH THE WEEK AS WELL,
STARTING AROUND 70 ON SUNDAY NIGHT AND FALLING INTO THE MID 50S-
LOW 60S THURSDAY NIGHT.
AVIATION
[THROUGH 00Z SATURDAY]
VFR CONDITIONS WILL PREVAIL FOR MOST OF TONIGHT. LATE NIGHT MVFR
OR IFR CONDITIONS DUE TO FOG/LOW CLOUDS ARE POSSIBLE 08Z-12Z
INLAND...MAINLY AT GNV AND VQQ. SCATTERED SHOWERS AND THUNDERSTORMS
ARE EXPECTED ON FRIDAY...MORE LIKELY AFTER 17Z.
MARINE
WAVES WILL CONTINUE TO SLOWLY FALL BELOW 7 FT THROUGH THE EVENING
HOURS, WHILE SOUTHEAST WINDS AROUND 15 TO 20 KNOTS PREVAIL
TONIGHT AND INTO FRIDAY AHEAD OF OUR NEXT COLD FRONT. A MORE
ACTIVE PATTERN FOR SHOWERS AND THUNDERSTORMS IS SETTING UP AS A
SERIES OF COLD FRONTS ROLL ACROSS THE COASTAL WATERS THE NEXT FEW
DAYS, WITH THE STRONGEST FRONT ON TUESDAY. CHANCE TO SLIGHT CHANCE
FOR SHOWERS AND THUNDERSTORMS ANTICIPATED THROUGH TUESDAY.
RIP CURRENTS: HIGH RISK OF RIP CURRENTS AT ALL AREA BEACHES
TODAY THROUGH FRIDAY, THEN RISK SHOULD DECREASE OVER THE WEEKEND.
HYDROLOGY
ELEVATED WATER LEVELS WILL CONTINUE TO GRADUALLY LOWER THROUGH
THE ST. JOHNS RIVER BASIN. TIDAL GAUGE AT BUFFALO BLUFF PEAKED IN
MINOR FLOOD AT 1.64 FT AROUND 11 AM THIS MORNING AND IS TRENDING
DOWN. MINOR FLOODING AROUND 1-1.5 FT MHHW WILL REMAIN POSSIBLE,
MOSTLY IN PUTNAM AND FLAGLER COUNTY THROUGH FRIDAY WITH NUISANCE
FLOODING OF LESS THAN A FOOT POSSIBLE FURTHER NORTH.
PRELIMINARY POINT TEMPS/POPS
AMG 71 88 71 88 70 / 20 70 40 20 0
SSI 75 85 74 85 73 / 20 50 30 30 10
JAX 72 90 72 89 73 / 10 50 40 30 0
SGJ 75 88 74 88 73 / 20 50 40 30 10
GNV 72 91 72 90 71 / 10 60 30 40 0
OCF 72 91 72 90 73 / 10 60 30 40 0
JAX WATCHES/WARNINGS/ADVISORIES
FL...HIGH RIP CURRENT RISK THROUGH FRIDAY EVENING FOR COASTAL DUVAL-
COASTAL FLAGLER-COASTAL NASSAU-COASTAL ST. JOHNS.
COASTAL FLOOD ADVISORY UNTIL 11 PM EDT FRIDAY FOR INLAND FLAGLER-
PUTNAM.
GA...HIGH RIP CURRENT RISK THROUGH FRIDAY EVENING FOR COASTAL CAMDEN-
COASTAL GLYNN.
AM...NONE.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page