799  
FXUS62 KJAX 181812  
AFDJAX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE JACKSONVILLE FL  
212 PM EDT FRI JUL 18 2025  
   
..HEAT ADVISORY THROUGH 6 PM FOR PORTIONS OF INLAND NE FL
 
   
..A FEW STRONG STORMS POSSIBLE LATE THIS AFTERNOON AND EVENING
 
 
...DANGEROUSLY HIGH HEAT INDICES AREA-WIDE THIS WEEKEND AND EARLY  
NEXT WEEK...  
 
FOR THE LATEST NE FL AND SE GA DAILY KEY MESSAGES PLEASE VISIT:  
HTTPS://WWW.WEATHER.GOV/MEDIA/JAX/BRIEFINGS/NWS-JAX-BRIEFING.PDF  
   
SYNOPSIS
 
 
ISSUED AT 213 PM EDT FRI JUL 18 2025  
 
NOON SURFACE ANALYSIS DEPICTS HIGH PRESSURE (1024 MILLIBARS)  
POSITIONED TO THE EAST OF THE GULF STREAM WATERS OFF THE  
SOUTHEASTERN SEABOARD. MEANWHILE, THE REMNANT CIRCULATION OF  
INVEST 93L WAS MEANDERING THROUGH THE LOWER MISSISSIPPI VALLEY.  
ALOFT...RIDGING CENTERED FROM THE SOUTHEASTERN SEABOARD SOUTHWARD  
THROUGH THE BAHAMAS CONTINUES TO GRADUALLY RETROGRADE WESTWARD,  
WITH THIS FEATURE STEERING A WEAK TROUGH SLOWLY NORTHWARD ACROSS  
EASTERN PORTIONS OF THE GULF AND FL PENINSULA. LATEST GOES-EAST  
DERIVED TOTAL PRECIPITABLE WATER IMAGERY INDICATES THAT DEEP  
TROPICAL MOISTURE REMAINS IN PLACE ACROSS OUR AREA, WITH PWATS  
GENERALLY AROUND OR JUST ABOVE 2 INCHES, WHILE LOWER VALUES IN THE  
1.6 - 1.8 INCH RANGE WERE ADVECTING NORTHWARD FROM THE INTERSTATE  
4 CORRIDOR IN CENTRAL FL. TEMPERATURES HAVE SOARED TO THE 90-95  
DEGREE RANGE AT MOST INLAND LOCATIONS AS OF 18Z, WITH DEWPOINTS  
IN THE 70S YIELDING HEAT INDEX VALUES IN THE 100-108 DEGREE  
RANGE THUS FAR THIS AFTERNOON. WHILE A HEALTHY CUMULUS FIELD WAS  
BUILDING ACROSS OUR REGION, CONVECTION THUS FAR AS REMAINED TO THE  
WEST OF THE SUWANNEE AND ALAPAHA RIVERS, WHERE INITIATION WAS  
BEING TRIGGERED BY THE INLAND MOVING GULF COAST SEA BREEZE  
BOUNDARY.  
 

 
   
NEAR TERM
 
 
(THROUGH TONIGHT)  
ISSUED AT 213 PM EDT FRI JUL 18 2025  
 
ALTHOUGH SUBSIDENCE WILL BE STRENGTHENING WITH THE RETROGRADING  
RIDGE APPROACHING OUR REGION, SOME COOLING ALOFT ASSOCIATED WITH  
WEAK TROUGHING ALOFT APPROACHING FROM THE SOUTH AND PLENTY OF LOW  
LEVEL MOISTURE SHOULD RESULT IN SCATTERED LATE AFTERNOON AND  
EVENING CONVECTION DEVELOPING ALONG INLAND MOVING SEA AND RIVER  
BREEZE BOUNDARIES, WITH A SLIGHTLY HIGHER COVERAGE POSSIBLE  
TOWARDS SUNSET ALONG THE U.S. HIGHWAY 301 CORRIDOR, WHERE  
MESOSCALE BOUNDARIES ARE LIKELY TO COLLIDE. SOUTHWESTERLY STEERING  
FLOW COULD BRING SOME OF THIS ACTIVITY BACK TOWARDS THE I-95  
CORRIDOR AFTER SUNSET BEFORE ACTIVITY DIMINISHES LATER THIS  
EVENING, OR BEFORE MIDNIGHT. A FEW STORMS WILL PULSE AS  
CONVECTIVE BOUNDARIES COLLIDE AND MAY BRIEFLY BECOME STRONG EARLY  
THIS EVENING, WITH STRONGER STORMS BEING CAPABLE OF PRODUCING  
DOWNBURST WINDS OF 40-50 MPH, FREQUENT LIGHTNING STRIKES, AND  
LOCALLY HEAVY DOWNPOURS. DEBRIS CLOUDINESS FROM THIS EVENING'S  
SCATTERED CONVECTION WILL THEN GRADUALLY THIN OUT OVERNIGHT, WITH  
LOWS ONLY FALLING TO THE MID 70S INLAND, RANGING TO AROUND 80 AT  
AREA BEACHES.  
 

 
   
SHORT TERM
 
 
(SATURDAY THROUGH SUNDAY)  
ISSUED AT 213 PM EDT FRI JUL 18 2025  
 
THIS WEEKEND, LOW/MID LEVEL RIDGING WILL SHIFT FROM THE ATLANTIC  
OVER SOUTHERN PORTIONS OF THE AREA CENTERED OVER CENTRAL TO NORTH  
CENTRAL FL AND THEN SHIFT WESTWARD INTO THE NE GULF WATERS. THIS  
WILL LIMIT CHANCES FOR T'STORMS TO MAINLY UNDER 30 PERCENT OVER  
NORTH CENTRAL FL AND UNDER 20 PERCENT OVER NE FL WITH SILENT POPS  
UNDER 10 PERCENT OVER MOST OF SE GA. SKY COVER WILL BE MOSTLY SUNNY  
UNDER THE HIGH AND ALONG WITH RISING HEIGHTS UNDER THE RIDGE WILL  
ALLOW HIGH TEMPERATURES TO RISE INTO THE MID TO UPPER 90S ON  
SATURDAY AND UPPER 90S TO AROUND 100 DEGREES INLAND. WEST TO SW  
FLOW WILL WILL PIN THE ATLANTIC SEABREEZE TO THE IMMEDIATE COAST  
SATURDAY AND OFFSHORE ON SUNDAY ALLOWING HIGHS TO REACH THE LOW TO  
MID 90S EVEN AT THE BEACHFRONT.  
 
THE MAIN STORY WILL BE THE HEAT INDEX VALUES THIS WEEKEND AS THE  
HIGH TEMPERATURES ALSO COMBINE WITH DEWPOINTS IN THE MID 70S TO  
CREATE HEAT INDEX VALUES 108-112 DEGREES ACROSS MUCH OF THE AREA,  
EXCEPT GENERALLY NORTH AND WEST OF WAYCROSS. THEREFORE, HEAT  
ADVISORIES ARE LIKELY FOR A MAJORITY OF NE FL AND ALONG THE SE GA  
COAST.
 
   
LONG TERM
 
 
(MONDAY THROUGH THURSDAY)  
ISSUED AT 213 PM EDT FRI JUL 18 2025  
 
NEXT WEEK, THE LOW/MID LEVEL RIDGE WILL SLIDE WESTWARD INTO THE  
NORTH CENTRAL GULF AS A TROUGH/WEAK FRONTAL BOUNDARY SETTLES  
SOUTHWARD ALONG THE SOUTHEAST U.S. COAST TOWARDS THE AREA.  
 
FOR MONDAY, SCATTERED TO NUMEROUS SHOWERS AND T'STORMS WILL  
DEVELOP AS MOISTURE POOLS AHEAD OF THE TROUGH/FRONT WITH PWATS  
CLIMBING TO 2.0 - 2.25 INCHES (90TH PERCENTILE THIS TIME OF  
YEAR). WINDS WILL SHIFT MORE EASTERLY AS THE FRONT APPROACHES FROM  
THE NORTH WITH HIGHEST T'STORM CHANCES WEST OF HIGHWAY 301.  
 
BY TUESDAY AND WEDNESDAY, THE FRONT WILL SLIDE INTO THE AREA WITH  
PWATS REACHING NEAR DAILY MAX VALUES (ABOVE 2.3-2.4 INCHES). THE  
COMBINATION OF HIGH MOISTURE, LIFT FROM THE FRONT AND SHORTWAVE  
ENERGY ALOFT WITH A MID/UPPER TROUGH MOVING SE OFF THE EASTERN  
SEABOARD WILL PROMOTE WIDESPREAD SHOWERS AND T'STORMS OVER OUR  
AREA EACH DAY. WHILE MID LEVEL TEMPS WILL STAY NEAR TO SLIGHTLY  
WARMER THAN CLIMATOLOGY (ABOUT -5 TO -7 CELSIUS), STEEP LOW LEVEL  
LAPSE RATES AND HIGH MOISTURE WILL ALLOW FOR STRONG DOWNBURST  
WINDS TO OCCUR BETWEEN SEABREEZE AND STORM OUTFLOW COLLISIONS  
ALONG WITH LOCALLY HEAVY RAINFALL FROM HEAVY DOWNPOURS AND  
FREQUENT LIGHTNING.  
 
ON THURSDAY, THE FRONT WILL BEGIN TO WEAKEN WITH SOME DRIER AIR  
WORKING IN FROM THE NORTH INTO SE GA AS WEAK HIGH PRESSURE EXTENDS  
FROM NEAR COASTAL NEW ENGLAND INTO THE CAROLINAS. THIS WILL LIMIT  
CHANCES TO SCATTERED T'STORMS OVER SE GA AND SCATTERED TO NUMEROUS  
T'STORMS ACROSS NE FL.  
 
TEMPERATURES WILL BEGIN THE PERIOD ABOVE NORMAL AS HIGHS REMAIN IN  
THE MID TO UPPER 90S AWAY FROM THE COAST WITH HIGH HEAT INDEX VALUES  
POTENTIALLY INTO HEAT ADVISORY LEVELS MONDAY BEFORE HIGHS TREND BACK  
TO NEAR TO SLIGHTLY ABOVE NORMAL TUESDAY THROUGH THURSDAY.  

 
   
AVIATION
 
 
(18Z TAFS)  
ISSUED AT 125 PM EDT FRI JUL 18 2025  
 
VFR CONDITIONS WILL PREVAIL AT THE REGIONAL TERMINALS THROUGH AT  
LEAST 20Z. SCATTERED SHOWERS AND THUNDERSTORMS WILL BEGIN  
DEVELOPING ALONG THE INLAND MOVING ATLANTIC AND GULF COAST SEA  
BREEZE BOUNDARIES AFTER 20Z, LIKELY ALONG THE I-95 AND I-75  
CORRIDORS. CONFIDENCE WAS HIGH ENOUGH TO MAINTAIN PROB30 GROUPS  
FOR BRIEFLY GUSTY WINDS AND MVFR CONDITIONS DURING HEAVIER  
DOWNPOURS AT THE REGIONAL TERMINALS, EXCEPT AT GNV, WHERE  
CONFIDENCE WAS ONLY HIGH ENOUGH FOR VICINITY COVERAGE LATE THIS  
AFTERNOON AND EARLY THIS EVENING. ACTIVITY MAY LINGER AT THE  
REGIONAL TERMINALS THROUGH AROUND 03Z. VFR CONDITIONS SHOULD  
THEN PREVAIL BY 04Z. PERIODS OF MVFR VISIBILITIES ARE THEN  
EXPECTED AT VQQ DURING THE PREDAWN AND EARLY MORNING HOURS ON  
SATURDAY. SOUTHEASTERLY SURFACE WINDS SUSTAINED AT 10-15 KNOTS  
WILL CONTINUE THROUGH AROUND 23Z AT THE SSI AND SGJ COASTAL  
TERMINALS. THE ATLANTIC SEA BREEZE BOUNDARY WILL PROGRESS SLOWLY  
INLAND THIS AFTERNOON, WITH SURFACE WINDS AT THE DUVAL COUNTY  
TERMINALS SHIFTING TO SOUTHEASTERLY AROUND 10 KNOTS BY 22Z. THE  
GULF COAST SEA BREEZE BOUNDARY WILL CROSS THE GNV TERMINAL TOWARDS  
21Z, SHIFTING SURFACE WINDS TO SOUTHWESTERLY AT 10-15 KNOTS.  
SURFACE WINDS WILL THEN SHIFT TO SOUTHERLY AFTER 00Z AT THE  
REGIONAL TERMINALS, WITH SPEEDS DIMINISHING OVERNIGHT AT THE  
INLAND TERMINALS AND REMAINING SUSTAINED AROUND 5 KNOTS AT THE  
COASTAL TERMINALS. WESTERLY SURFACE WINDS WILL THEN DEVELOP  
TOWARDS SUNRISE AT THE COASTAL TERMINALS AND BY 14Z AT THE INLAND  
TERMINALS.  
 

 
   
MARINE
 
 
ISSUED AT 1229 PM FRI JUL 18 2025  
 
HIGH PRESSURE CENTERED OFF THE SOUTHEASTERN SEABOARD WILL SHIFT  
SLOWLY WESTWARD TOWARDS OUR LOCAL WATERS TONIGHT AND SATURDAY.  
ONLY ISOLATED LATE AFTERNOON AND EVENING THUNDERSTORMS ARE  
POSSIBLE ACROSS THE NEAR SHORE WATERS THROUGH SATURDAY. TROUGHING  
WILL THEN DEVELOP ON SUNDAY OVER THE SOUTHEASTERN STATES, WITH  
THIS FEATURE POTENTIALLY SHARPENING NEAR OUR LOCAL WATERS EARLY  
NEXT WEEK. CHANCES FOR SHOWERS AND THUNDERSTORMS WILL INCREASE  
BEGINNING LATE SUNDAY AFTERNOON, WITH STRONG TO ISOLATED SEVERE  
AFTERNOON AND EVENING THUNDERSTORMS POTENTIALLY IMPACTING OUR  
LOCAL WATERS EACH DAY NEXT WEEK. SEAS OF 2 TO 3 FEET WILL PREVAIL  
BOTH NEAR SHORE AND OFFSHORE DURING THE NEXT SEVERAL DAYS.  
 
RIP CURRENTS: A PERSISTENT EAST-SOUTHEASTERLY OCEAN SWELL WILL  
COMBINE WITH DEVELOPING ONSHORE WINDS THIS AFTERNOON TO CREATE A  
LOWER END MODERATE RISK AT ALL AREA BEACHES. SIMILAR CONDITIONS  
ARE EXPECTED ON SATURDAY, WITH A LOW RISK POSSIBLE BY SUNDAY AND  
MONDAY DUE TO LOW SURF HEIGHTS.  
 

 
   
FIRE WEATHER
 
 
ISSUED AT 1229 PM FRI JUL 18 2025  
 
SOUTHWESTERLY TRANSPORT SPEEDS AROUND 10 MPH THIS AFTERNOON WILL  
COMBINE WITH ELEVATED MIXING HEIGHTS TO CREATE GENERALLY FAIR  
DAYTIME DISPERSION VALUES, EXCEPT GOOD VALUES FOR LOCATIONS NORTH  
OF WAYCROSS IN SOUTHEAST GA AND POOR VALUES AT COASTAL LOCATIONS,  
WHERE ONSHORE SURFACE WINDS WILL DEVELOP BY MID-AFTERNOON. SURFACE  
AND TRANSPORT WINDS WILL BECOME WEST-SOUTHWESTERLY ON SATURDAY,  
WITH BREEZY TRANSPORT SPEEDS DEVELOPING NORTH OF THE I-10 CORRIDOR  
DURING THE AFTERNOON HOURS. THESE BREEZY CONDITIONS WILL COMBINE  
WITH ELEVATED MIXING HEIGHTS TO CREATE HIGH DAYTIME DISPERSION  
VALUES ACROSS MOST OF INLAND SOUTHEAST GA, WHILE GOOD VALUES  
PREVAIL ELSEWHERE FOR INLAND LOCATIONS, EXCEPT FAIR VALUES FOR  
LOCATIONS SOUTH OF THE I-10 CORRIDOR, WHERE SPEEDS WILL REMAIN  
LIGHT. SURFACE AND TRANSPORT WINDS WILL THEN SHIFT TO WESTERLY ON  
SUNDAY, WITH BREEZY TRANSPORT SPEEDS COMBINING WITH ELEVATED  
MIXING HEIGHTS TO CREATE HIGH DAYTIME DISPERSION VALUES FOR INLAND  
LOCATIONS ALONG AND NORTH OF I-10, WITH GOOD VALUES FORECAST  
ELSEWHERE. AFTERNOON AND EVENING THUNDERSTORM COVERAGE WILL  
INCREASE NEXT WEEK.  
 

 
   
CLIMATE
 
 
ISSUED AT 1229 PM FRI JUL 18 2025  
 
DAILY RECORD HIGH TEMPERATURES AT OUR DESIGNATED CLIMATE SITES  
THROUGH TUESDAY, JULY 22  
 
TODAY SATURDAY SUNDAY MONDAY TUESDAY  
---------------------------------------------------  
JACKSONVILLE 100/1887 101/2000 103/2000 102/1942 101/1942  
GAINESVILLE 100/1889 101/1899 100/1942 102/1942 99/1907  
ALMA, GA 102/2000 102/2002 104/2000 102/1942 100/1942  
CRAIG AIRPORT 98/1981 99/1993 100/2000 98/2015 99/1977  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
AMG 74 98 75 98 / 10 10 0 10  
SSI 79 95 79 96 / 10 10 0 10  
JAX 76 99 77 100 / 10 20 0 10  
SGJ 76 95 77 96 / 10 20 0 10  
GNV 74 97 74 98 / 10 20 0 10  
OCF 75 95 75 96 / 10 30 0 20  
 

 
   
JAX WATCHES/WARNINGS/ADVISORIES
 
 
FL...HEAT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR FLZ023-030-031-038-  
132-137-225-232-237-325-425-433-533-633.  
 
GA...NONE.  
AM...NONE.  

 
 

 
 
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