FXUS62 KJAX 210431 AFDJAX Area Forecast Discussion National Weather Service Jacksonville FL 1231 AM EDT Sun Jun 21 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 - Scattered to Numerous Thunderstorms this afternoon and evening (2 PM to 9 PM). Strong Storms with Gusty Winds, Frequent Lightning Strikes & Heavy Downpours - Hot and humid next week with Heat Advisory headlines possible && .NEAR TERM /THROUGH TONIGHT/... Main Highlights Today and Tonight: - Scattered to Numerous Storms this afternoon and evening - Main Hazards are locally heavy rainfall and gusty winds West to Southwest flow to the south of stationary boundary over the SE US states along with a moist airmass with PWATs around 2 inches will once again support another round of scattered to numerous showers and storms this afternoon and evening, the main focus for the heavier storms will be once again along the I-95/US-17 corridors near the Atlantic Coast. A few strong to isolated storms will be possible with gusty winds to 50 mph and the moist airmass will support locally heavy rainfall with isolated totals of 2-3 inches possible, but not organized enough to support any issuance of flood watches at this time. Convection will move offshore into the Atlantic after sunset Sunday evening with generally fair skies and quiet weather conditions expected for late Sunday Night. Temps are expected to remain at near normal values with lows in the 70s and Max temps in the upper 80s/near 90F across SE GA and into the lower 90s across NE FL, mainly south of the I-10 corridor. Heat indices are expected to peak in the 100-105F range this afternoon, below any heat advisory criteria. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... Main Highlights This Period: - Lower rainfall coverage on Monday - Heat Advisory conditions possible Showers and storms will become less widespread on Monday and Tuesday as prevailing flow shifts to become more westerly and relatively drier air filters across the forecast area and reducing PWAT values over the forecast area. High temperatures for the beginning of the week will be in the lower to mid 90s over southeast Georgia and in the mid to upper 90s over northeast Florida. Overnight low temperatures will drop down into the mid 70s over inland areas and in the mid to upper 70s along the coastline. Heat index values are expected to rise to be over 100 with a likely chance for Heat Advisory conditions on Monday and Tuesday. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... Main Highlights This Period: - Heat Advisory conditions possible through the end of the week - Return to at least scattered afternoon storms mid to late week Predominantly westerly flow will continue on through the end of the week and into the weekend with daily bouts of diurnal showers and storms, stronger developments occurring along the seas breeze boundary and areas of collision, with a potential for relatively more widespread convection by Thursday as a stretched longwave trough passes over the region. Daily high temperatures temperatures are expected to consistently rise to above average levels with max temps in the lower to mid 90s. Heat Advisory conditions seem likely through the end of the week and into the weekend as heat index values rise to levels of over 100. && .AVIATION /06Z SUNDAY THROUGH 06Z MONDAY/... Generally VFR conds this morning with convective debris clouds across most of the terminal locations, which should prevent any significant fog formation around sunrise. Another round of storms is expected this afternoon and expect the need to keep PROB30 groups in place generally in the 18-24Z time frame for possible MVFR conds in TSRAactivity along with gusty winds to 25-30 knots. After sunset Sunday evening expect mainly VFR conds with dissipating convective debris clouds through the end of the TAF period. && .MARINE... A frontal boundary will shift north of the waters Today. Weak high pressure ridge will slowly build in over the area waters Monday and into Tuesday with isolated to scattered thunderstorms returning by midweek as another front moves in from the north. Stronger offshore winds with exercise caution level winds looks possible for offshore waters Monday into Tuesday. Rip Currents: Rip current risk is expected to remain on the low side with the predominant offshore flow and surf/breakers 1-2 ft early this week. && .FIRE WEATHER... HIGH DAYTIME DISPERSION VALUES ON MONDAY OCCURRING NORTH OF I-10 Showers and storms will build in a west to east pattern today with more widespread developments occurring in the afternoon with daytime heating and along boundaries and areas of convergence. More inhibited convection is expected for Monday with higher dispersion values for portions of southeast Georgia and bordering areas of northeast Florida. FOG POTENTIAL AND OTHER REMARKS: Areas that receive heavier rainfall may also experience patchy late-night and early-morning fog. Thunderstorms will produce locally gusty winds, frequent lightning, and locally heavy downpours. && .PRELIMINARY POINT TEMPS/POPS... AMG 88 71 91 76 / 60 30 20 10 SSI 87 75 93 79 / 50 40 30 0 JAX 90 73 95 77 / 60 30 30 0 SGJ 91 74 95 77 / 70 30 30 0 GNV 91 73 94 75 / 60 20 20 0 OCF 92 73 94 76 / 50 20 10 0 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. MARINE...None. && $$