textproduct: Jacksonville

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

- Hot Today with Peak Heat Index Values 103 to 107 degrees

- Isolated Strong Storm I-75 Corridor This Afternoon

- Daily Mainly Afternoon & Evening Thunderstorms. Tue -Thu: Mainly Inland Northeast Florida (between HWY 301 & I-75). Fri Weekend: Increasing chances including Southeast GA

- Moderate Rip Current Risk SE GA & NE FL Beaches Today

- Minor River Flooding for Satilla River

NEAR TERM /THROUGH TONIGHT/

Main Highlights Today and Tonight:

- Isolated strong storm potential I-75 corridor this afternoon

A "backdoor" cool front currently over the SE GA waters will continue to shift south today as surface high pressure wedges southward down the southeastern seaboard developing a surge of NE winds in the wake of the front. This flow change will allow the Atlantic sea breeze to become dominant shifting well inland by the afternoon hours. Isolated showers and storms develop along the sea breezes in the late morning to early afternoon hours, increasing in coverage as boundaries interact late afternoon. Subsidence from lingering strong ridging aloft and slightly drier air will limit convective coverage in SE GA today. The highest rain chances will focus along and west of the I-75 corridor deeper moisture combines with the sea breeze merger. An isolated strong storm will also be possible this afternoon along mergers with any additional lift provided by the passing frontal zone in north-central FL. Convection will shift into the Gulf this evening with only a few spotty showers lingering in its wake. In NE flow, highs will range from the upper 80s along the coast to the mid 90s further inland. Slightly lower heat indices today expecting to remain just below criteria in the 100-107 F range. Above seasonable overnight lows continue in the 70s.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/

Main Highlights This Period:

- Breezy East Winds & Elevated Rip Current Risk - Inland Strong Afternoon & Evening Storms

A drier airmass will remain in place on Wednesday, particularly along and north of the Interstate 10 corridor, supporting mostly dry conditions across southeast Georgia and much of northern northeast Florida. The best chances for afternoon and evening showers and thunderstorms will be confined to inland north-central Florida, where deeper moisture lingers. An easterly onshore flow will continue, with northeast winds of 10 to 15 mph and occasional gusts up to 25 mph, especially near the coast. High temperatures will range from around 90 degrees at the beaches to the mid and upper 90s inland. Despite the hot temperatures, lower dewpoints mixing into the lower 70s and even the upper 60s across portions of southeast Georgia during the afternoon will keep peak heat index values generally between 100 and 105 degrees, remaining below local Heat Advisory criteria. Overnight lows will settle into the middle 70s.

Thursday: A broad upper-level trough approaching Florida from the east, combined with persistent mid-level ridging anchored north and northeast of the region, will maintain an easterly steering flow and a dominant Atlantic sea breeze. While moisture will gradually increase across northeast Florida, overall shower and thunderstorm coverage is expected to remain lower than typical, with rain chances generally 2040 percent south of State Road 16. Isolated showers may develop near the northeast Florida coast during the morning before activity shifts inland during the afternoon and evening, primarily across inland northeast Florida south of State Road 16. Southeast Georgia will remain under the greater influence of the ridge, resulting in warmer and drier conditions with little to no rainfall expected. High temperatures will reach the lower 90s along the coast and the mid to upper 90s inland, with peak heat index values climbing into the upper 90s to around 102 degrees across northeast Florida, remaining just below local Heat Advisory criteria.

LONG TERM /FRIDAY THROUGH MONDAY/

Main Highlights This Period:

- Higher Rain Chances Return for Northeast FL Friday - Scattered to Numerous Showers and Storms this coming weekend - Building Heat for Southeast GA

On Friday, a low level trough will bisect the CWA from Trenton to Saint Simons to enhance moisture and shower and thunderstorm coverage across northeast Florida while southeast Georgia remains on the northern fringe of the deeper moisture beneath a strong ridge. Easterly steering flow will persist, with convection becoming more numerous across northeast Florida and less tied to the traditional sea breeze pattern. Southeast Georgia will experience warmer temperatures and comparatively lower rain chances. Heat index values across portions of northeast Florida will be in 98 to 106 degree range.

During the Independence Day weekend, the upper-level trough is forecast to drift farther west while subtropical ridging rebuilds offshore of the Southeast coast. As a result, low-level winds will gradually veer from south-southeasterly to south-southwesterly, allowing deeper tropical moisture to expand northward across both northeast Florida and southeast Georgia. This pattern will support increasing daily coverage of afternoon and evening showers and thunderstorms across the entire forecast area.

For Independence Day, current indications favor the highest thunderstorm coverage developing across northeast Florida during the afternoon before shifting inland during the evening. Weak steering currents may result in slow-moving storms capable of producing prolonged periods of heavy rainfall, frequent lightning, and localized flooding where storms persist. Temperatures will trend warmer through the holiday weekend, with highs climbing into the middle and upper 90s. Daily peak heat index values will generally range from 105 to 110 degrees, approaching or exceeding local Heat Advisory criteria, particularly across northeast Florida.

By Monday, southwesterly flow pattern continues with abundant moisture, and scattered to numerous afternoon and evening showers and thunderstorms across both southeast Georgia and northeast Florida. High temperatures will remain in the mid-90s, with heat index values once again reaching 105 to 110 degrees, maintaining the potential for Heat Advisories.

AVIATION /06Z TUESDAY THROUGH 06Z WEDNESDAY/

Light rain will linger over CRG for the next hour. Otherwise mainly VFR conds with mid/high convective debris clouds and light and variable winds expected through sunrise and only patchy MVFR fog possible at VQQ from 08-11Z. ENE winds quickly increase after 12Z pushing the Atlantic sea breeze well inland and to GNV by 18Z. Winds will be sustained about 10-15 kts with gusts 15-20 kts. Highest winds will be along the coast. With the Atlantic sea breeze shifting in early, chances for showers and storms will be confined mainly to VQQ and GNV. Have TEMPOs in from 17-22Z for breezy winds and lower CIGs/VSBYs for VQQ/GNV.

MARINE

A backdoor front will push into the southeast Georgia waters this morning and shift south of the northeast Florida waters later this afternoon. A surge of northeasterly winds develop in the wake of the front and continues into Wednesday. The onshore flow will keep thunderstorm activity mainly on land through the middle of the week. The front lifts back northward into the area as remnant inverted trough on Thursday resulting in an increase in rain and storm chances. As surface high pressure builds to the south, a weak southwesterly flow will develop into the Independence Day holiday weekend and increase chances for thunderstorms.

Rip Currents:

Persistent and breezy northeasterly winds Today will yield a solid moderate risk of rip currents at all area beaches, with a potential high risk on Wednesday as surf builds to 3 to 5 feet.

FIRE WEATHER

DAILY LOCALIZED HIGH DISPERSION SUWANNEE VALLEY AND INTERIOR SE - Georgia This Afternoon And Tuesday Afternoon

Easterly winds will continue through Wednesday, increasing during the afternoon with the inland progression of the Atlantic sea breeze. Wind gusts up to 25 mph will be possible, especially near the coast and extending inland toward the St. Johns River basin. A drier airmass will support mostly dry conditions Wednesday across areas north of Interstate 10, including the Okefenokee National Wildlife Refuge and the Osceola National Forest, while the greatest afternoon and evening thunderstorm coverage will be confined to north-central Florida, including the Ocala National Forest. Minimum relative humidity values will remain above critical fire weather thresholds, although localized high daytime dispersion is expected each afternoon north of Interstate 10.

Fog Potential: Significant fog development is not anticipated through the period. Any stronger thunderstorms will be capable of producing frequent lightning, heavy rainfall, and strong, erratic wind gusts, particularly during the afternoon and evening hours.

HYDROLOGY

Minor flooding continues along the Satilla River near Atkinson.

PRELIMINARY POINT TEMPS/POPS

AMG 94 72 94 70 / 30 10 0 0 SSI 88 79 89 78 / 10 10 0 10 JAX 91 75 91 75 / 20 10 10 10 SGJ 90 77 90 77 / 10 20 50 20 GNV 94 74 93 72 / 70 10 30 0 OCF 94 74 92 73 / 80 20 40 0

JAX WATCHES/WARNINGS/ADVISORIES

FL...None. GA...None. MARINE...None.