Area Forecast Discussion
Issued by NWS Jacksonville, FL
Issued by NWS Jacksonville, FL
339 FXUS62 KJAX 221807 AFDJAX Area Forecast Discussion National Weather Service Jacksonville FL 207 PM EDT Wed Jul 22 2026 .KEY MESSAGES... For the latest NE FL and SE GA Daily Key Messages please visit: https:/www.weather.gov/media/jax/briefings/nws-jax-briefing.pdf - Seasonably Hot Conditions Continue through Friday. Afternoon Peak Heat Index Values of 100-107 Each Day. Possible Heat Advisory Conditions this Weekend and Early Next Week. - Moderate Rip Current Risk Continues through Thursday at Area Beaches. - Only Isolated to Widely Scattered Late Afternoon and Evening Thunderstorms Forecast through Friday. - Scattered Afternoon and Evening Thunderstorms this Weekend and Next Week. Few Strong Storms Possible Each Afternoon, Mainly Along the I-95 Corridor. && .NEAR TERM /THROUGH TONIGHT/... Main Highlights through Tonight: - Isolated Late Afternoon and Early Evening Thunderstorms Possible along the U.S.-301 Corridor in North Central and Northeast FL. Afternoon surface analysis depicts Tropical Storm Bertha (1000 millibars) moving westward over the far northern Gulf and approaching coastal Mississippi and Louisiana. Meanwhile, a wavy frontal boundary extends from New England southwestward through the Ohio, Tennessee, and lower Mississippi Valleys. Aloft...deep- layered Atlantic ridging was building westward across our region, while troughing over the Great Lakes and Ohio Valley was digging east- southeastward towards the Mid-Atlantic states. Otherwise, "heat wave" ridging was centered over the Southern Plains states. Latest GOES-East derived Total Precipitable Water imagery indicates that a Saharan Air Layer (SAL) has overspread most of our inland locations in the wake of departing Tropical Storm Bertha, with PWATs of 1.3 - 1.4 inches in place for locations west of U.S. Highway 301. A narrow pocket of moisture that is closer to late July climatology, featuring PWATs of 1.6 - 1.8 inches, was in place for locations east of U.S.-301. Brisk south-southwesterly low level flow was organizing cumulus cloud streets across most of our area, with mostly thin patches of cirrus cloud cover also filtering southward across our region. Temperatures at 17Z have climbed to the lower 90s at inland locations, while the Atlantic sea breeze has cooled most coastal locations to the upper 80s. Dewpoints have fallen to the upper 60s to around 70 for inland locations in southeast GA and the Suwannee Valley, while low to mid 70s prevail inland and mid to upper 70s were noted behind the inland moving sea breeze at coastal locations. The pocket of moisture trapped over locations east of U.S. Highway 301 in north central and northeast FL may be just enough to allow for isolated convection to develop late this afternoon or early this evening as the inland moving Atlantic and Gulf sea breeze boundaries potentially collide. Otherwise, the suppressing nature of the SAL in place over the rest of our area will provide for an unusually dry afternoon and evening. Any convection that does manage to develop over inland locations south of I-10 and east of I-75 will dissipate before midnight, with fair skies expected overnight area-wide. Lows at inland locations will only fall to the mid 70s, ranging to around 80 at area beaches. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... Main Highlights This Period: - Isolated to Widely Scattered Diurnal Thunderstorms Return Thursday and Friday For Inland Locations. - Seasonably Hot and Humid Weather Inland, Near Heat Advisory Along Coastal Counties. Drier air continues over much of the area on Thursday, although isolated to scattered convection is expected inland where the Gulf and Atlantic sea breezes interact, near the US-301 corridor in the afternoon then near I-75 later on. A front will be stalled over central Georgia, mainly enhancing moisture north of the local area, but southeast Georgia will see isolated convection again close to US-301. Elsewhere, across northeast Florida will be mainly rain free due to the ridging aloft and lower PWATs. Temperatures remain above normal both Thursday and Friday due to less cloud/storm coverage, highs will be in the mid to upper 90s inland, low 90s along the coast. Drier air will keep max afternoon heat index values around 105-108 degrees. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... Main Highlights This Period: - Increasing Chances for Afternoon and Evening Thunderstorms Late this Weekend and Early Next Week. - Potential Heat Advisory Conditions this Weekend. Westerly winds with the stalled front over Georgia will begin to return moisture to the area, increasing precipitation potential this weekend. Saturday, highest storm chances will be north of I-10, closer to the front. By Sunday, PWATs rise above 2.0" area-wide, with inland areas seeing precipitation chances around 30-50%. Closer to the coast, slightly higher storm chances will be possible as the westerly winds push the Gulf sea breeze towards the east coast where it will interact with the Atlantic sea breeze near I-95. Inland highs remain in the mid to upper 90s Saturday, and a few degrees cooler Sunday with the increase in convective coverage. Monday and Tuesday, it will be hot again with scattered storm chances primarily across northeast Florida. && .AVIATION /18Z WEDNESDAY THROUGH 18Z THURSDAY/... VFR conditions will prevail through at least 06Z Thursday at the regional terminals. Isolated showers and possibly a thunderstorm may develop west of the I-95 corridor after 22Z as the inland moving Gulf and Atlantic sea breeze boundaries potentially collide. Confidence remains too low to indicate anything other than vicinity showers at VQQ and GNV and this time. Periods of MVFR to IFR visibilities are then expected towards 07Z at VQQ. The Atlantic and Gulf sea breezes will progress inland this afternoon, with southeasterly surface winds increasing to around 15 knots at the SSI and SGJ coastal terminals after 19Z, while southerly surface winds at the Duval County terminals shift to southeasterly at 10-15 knots after 20Z. Southerly surface winds will then resume at the regional terminals by 00Z, with speeds remaining sustained around 10 knots at the coastal terminals through around 04Z, while speeds inland gradually diminish to around 5 knots or less by 06Z Thursday. Light and variable surface winds are forecast through the mid-morning hours on Thursday. && .MARINE... Southerly winds will shift to southeasterly this afternoon, with speeds again increasing to Caution levels both near shore and offshore towards sunset. Southerly winds will likely remain sustained at Caution levels through around midnight tonight. Winds will then gradually diminish overnight and Thursday as high pressure builds directly over our local waters. Unseasonably dry conditions will prevail through Friday night. A frontal boundary will then stall just north of the Georgia waters this weekend, with this feature potentially increasing chances for showers and thunderstorms through early next week. Prevailing westerly winds are expected by Sunday and Monday, with the afternoon sea breeze shifting winds across the near shore waters to southeasterly during the afternoon hours. Rip Currents: Longshore currents will persist through this afternoon, but surf will diminish to around 2-3 feet. Breezy onshore winds will create a moderate rip current risk through around sunset today at area beaches. Surf heights continue to lower another foot by Thursday, leading to a lower end Moderate risk following the passage of the afternoon sea breeze. && .FIRE WEATHER... A frontal boundary will approach on Thursday with widely scattered inland thunderstorms in the afternoon hours and again Friday afternoon. Increasing thunderstorm chances expected this weekend as the front sinks slowly into the area. Overall, dispersion is expected to be good through the weekend, with no minimum relative humidity concerns. Fog Potential and Other Remarks: Significant fog development is not expected for the next several nights. && .PRELIMINARY POINT TEMPS/POPS... AMG 74 96 75 96 / 0 0 0 10 SSI 80 93 80 94 / 10 0 0 0 JAX 76 96 76 96 / 10 20 0 10 SGJ 78 93 76 93 / 10 0 0 0 GNV 75 95 74 96 / 20 10 10 10 OCF 75 95 74 95 / 20 30 0 10 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. MARINE...None. && $$