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

- High Heat Risk Through The Weekend. Heat Index Values Rise to the 100-105 Range Today. Heat Advisory Conditions Possible Saturday Peak Heat Index: 104-108

- Moderate Rip Current Risk at Area Beaches Today

- Afternoon & Evening TStorms Area-Wide this Weekend into Next Week. Isolated Storms this Afternoon and Evening across North- Central FL. Strong Storms with Gusty Winds, Frequent Lightning Strikes & Heavy Downpours possible Along the I-95 Corridor beginning Saturday

NEAR TERM /THROUGH TONIGHT/

Main Highlights This Period:

- Continued Hot with Heat Index peaking around 102-107 degrees

- Widely scattered storms this afternoon and evening

Northwest steering flow will continue above normal temperatures reaching into the middle 90s area-wide this afternoon with peak heat indices close to 105F, but remaining below Heat Advisory criteria as dew point temps will mix down to around 70F this afternoon.

PWATs high enough in the 1.7 to 1.9 inch range today combined with sea breeze fronts pushing inland will trigger isolated storms across SE GA and scattered storms across NE FL, with best chances along the US 301 highway corridor/St. Johns River Basin over inland NE FL late this afternoon into the evening. Warm air aloft with 500 mb temps around -5C will keep convection on the weaker side, but a few strong storms with gusty winds to 40 mph, locally heavy rainfall and frequent lightning possible as the Gulf/East coast sea breezes merge across inland NE FL late this afternoon/evening.

Convection will fade over inland areas after sunset and likely end around midnight with skies remaining partly cloudy with some convective debris mid/high clouds through the overnight hours as temps remain above normal with lows generally only falling into the middle 70s inland and upper 70s along the Atlantic Coast.

SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/

Main Highlights This Period:

- Potential for a few strong to severe storms

- Heat indices values will approach Advisory levels

The region will be between high pressure to the southeast and a frontal boundary to the north Saturday and Sunday. This pattern will yield a southwest flow. The flow is not strong enough to the keep the east coast sea breeze from moving inland though. So, sea breeze collisions are expected in the afternoons. The combination of diurnal heating, increasing moisture and sea breeze interactions will lead to scattered to numerous showers and thunderstorms.

Temperatures will trend above seasonal averages this period.

LONG TERM /MONDAY THROUGH FRIDAY/

Main Highlights This Period:

- Daily thunderstorm chances, with a few strong to severe thunderstorms possible

The region will remain between high pressure to the southeast, and a frontal zone to the north Monday and Tuesday. This will continue the moist flow from the Gulf. The flow both days looks strong enough to keep the east coast sea breeze from moving inland. Convection on Monday and Tuesday will largely be driven by the Gulf sea breeze, and diurnal instability in a moist atmosphere.

The surface boundary will sink south into the area and stall Wednesday through Friday, as it diminishes in strength. The combination of diurnal instability, ample moisture, and boundary convergence will yield above average chances for convection.

Temperatures will trend above normal this period, except for highs on Tuesday and Wednesday due to convective coverage.

AVIATION /18Z FRIDAY THROUGH 18Z SATURDAY/

VFR conditions prevail this period. Otherwise, widely scattered convection breaking out along sea breeze fronts will support at least VCTS at all TAF sites this afternoon and will need to add PROB30 group at the GNV terminal as sea breeze fronts merge near this location later this afternoon in the 20-24Z time frame. VFR with convective mid/high clouds through the overnight hours, but still some potential for MVFR fog at VQQ in the 06-10Z time frame.

MARINE

A weakening front will stall north of the waters tonight and dissipate through the weekend as another front pushes into the southeastern US early next week. This will promote nightly southerly wind surges to Exercise Caution levels, mainly offshore through at least the middle part of next week. The predominantly offshore flow early next week will strengthen with the second front and increase chances for afternoon thunderstorms that are steered into and across the coastal waters.

Rip Currents:

Generally low to near moderate risk of rip currents today through the weekend, mainly during the afternoon with the sea breeze, combined with a moderate onshore but low amplitude swell.

FIRE WEATHER

PATCHY TO AREAS OF HIGH AFTERNOON DISPERSIONS SUNDAY THROUGH - Tuesday, Then Again Thursday And Friday

The region will be between high pressure to the southeast, and a frontal zone to the north through Tuesday. This front will settle across the area and stall Wednesday through Friday. Rounds of showers and thunderstorms are expected each day, with potential for a few strong to severe storms. FOG POTENTIAL AND OTHER REMARKS: Significant fog is not expected Tonight.

PRELIMINARY POINT TEMPS/POPS

AMG 75 96 77 95 / 20 30 30 50 SSI 79 94 79 93 / 10 50 20 50 JAX 76 97 77 96 / 20 60 20 70 SGJ 76 95 77 95 / 20 60 10 60 GNV 75 97 75 95 / 30 60 30 40 OCF 74 94 76 93 / 20 40 20 20

JAX WATCHES/WARNINGS/ADVISORIES

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