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

- Moderate Risk Of Rip Currents at All Area Beaches through Friday. Possible high risk at northeast Florida beaches during the weekend.

- Scattered to numerous afternoon and evening thunderstorms from Friday through the weekend and next week.

- Heat Indices of 100-105 Degrees Possible this Weekend.

NEAR TERM /UNTIL 6 AM FRIDAY MORNING/

Main Highlights This Period:

- Hot inland with scattered afternoon/evening storms

- Moderate Risk of rip currents at area beaches

Current satellite obs show PWATs currently hovering around 1.25" to 1.4" from the coast towards inland locations where some showers and storms have already developed over NE Marion County. Moisture levels are expected to continue to increase as PWATs rise into the 1.5" to 1.7" range. As the Atlantic and Gulf breeze push inland, more activity will likely begin to develop heading into the mid afternoon hours, with isolated storms along sea breeze mergers around the US- 301 corridor to I-75 corridor with the overall flow continuing from the south. With any storms that do develop, gusty winds of around 40- 50 mph will be possible. Temperatures have already rose to the mid to upper 80s, with a few locations potentially rising further to the lower 90s by peak heating. But increasing cloud cover and shower activity may put a damper on further heating. A few showers and storms may linger into the early evening hours but should clear by midnight. A few locations may see patchy fog develop during the overnight hours, but chances seem low at this time. Lows will dip into the lower to mid 70s with the warmer temperatures along the coast.

SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/

Main Highlights This Period:

- Daily thunderstorms each afternoon and evening - Hot and humid conditions

Fairly weak high pressure ridge axis will remain over the western Atlantic and over northern portions of Florida through the period. This will result in southeast to south winds for our area. Aloft, a mid level high over central FL with ridge extending northeast off our coast will tend to shift southeastward allowing for more southwesterly flow aloft for our area with at least a couple of weak glancing affects from shortwave perturbations in the mid to upper levels. PWAT values for inland areas remain favorable for convection upwards of 1.5 to 2 inches Friday and Saturday. Most of the convection will tend to converge toward inland areas and into southeast GA both days, mainly for the afternoon and evening time frame. Inland southeast GA has the highest rain chances, upwards of 40-60 percent Friday and 60-80 percent Saturday, while northeast FL is more in the 20-40 percent range Friday, and 40-70 percent Saturday. Lowest chances along the northeast FL coastal areas at about 25-35 percent. Mean steering flow is south to southwest about 10-15 mph. Isolated strong storms will be possible both days, perhaps a little better chance on Saturday with temps aloft slightly cooler at -9C, mid level lapse rates slightly steeper around 6.5 deg/km, and deep layer shear a bit higher near 25-30 kt.

Temperatures will be well above average this period with daily max temps reaching up into the lower to mid 90s over inland areas and in the upper 80s along the coast. Peak heat indices of about 95-100 are forecast. Overnight low temperatures will drop down into the lower 70s for inland areas and in the mid 70s for areas near the shoreline.

LONG TERM /SUNDAY THROUGH THURSDAY/

- Hot temperatures continue through the weekend and early next week

- Chances of showers and storms each day

The high pressure ridge axis across the southeast states and the western Atlantic will very slowly shift southward through the period and may have less influence on the area by mid to late week. Looks like a chance of showers and storms each day, possibly increasing chances by late in the period. Some drier air may build into the area Monday that leads to probable reduced POPs. Hot temperatures will persist through about Tuesday with inland highs in the lower 90s, and east coast highs in the mid to upper 80s. Max temps may trend a little lower by 2-3 degrees Wednesday into Thursday.

AVIATION /00Z FRIDAY THROUGH 00Z SATURDAY/

Showers and thunderstorms developing across north central FL early this evening are expected to remain south of the GNV terminal, and we currently indicate vicinity thunderstorm coverage at GNV through around 01Z. A brief light shower will otherwise be possible at VQQ through around 01Z, but confidence was too low to indicate anything other than vicinity coverage at this time. Otherwise, VFR conditions will prevail at the regional terminals through at least 08Z. Periods of MVFR to IFR visibilities will be possible at VQQ during the predawn hours. Brief periods of MVFR ceilings around 2,500 feet will be possible at the regional terminals after 14Z, with confidence high enough to indicate a period of prevailing ceilings at SGJ from around 15Z through around 17Z. Showers and thunderstorms will then develop near the northeast FL terminals after 17Z, with potential impacts initially at GNV possible towards 18Z, with activity then spreading towards the Duval County terminals and SGJ after 19Z. Confidence was too low to indicate anything other than PROB30 groups for brief wind gusts up to 30 knots and MVFR conditions during heavier downpours. VFR conditions will likely prevail at SSI through the TAF period. Southeasterly surface winds sustained around 10 knots outside of shower and thunderstorm activity this evening will shift to southerly at 5-10 knots by 03Z before diminishing at the inland terminals overnight. Southerly winds of 5-10 knots will then redevelop shortly after sunrise on Friday at the regional terminals.

MARINE

High pressure will be centered to the east northeast through the weekend. This will bring mainly southeast to south flow through the weekend with a daily sea breeze near the Atlantic Coast. Winds are expected to increase to small craft exercise caution criteria on Friday afternoon and persist through the weekend.

Rip Currents:

Moderate risk of rip current continues Today for area beaches. A High risk by Friday and through the weekend for northeast Florida beaches may be needed as the surf may see a bit of a rise with the surf averaging around 3 feet to possible 4 ft.

FIRE WEATHER

The combination of deep mixing and sufficient south and southeast transport winds will result in generally good to very good dispersions each afternoon through the weekend. Persistent onshore flow will allow moisture to continue filtering into the area, leading to MinRH values remaining above critical levels. With the onshore flow from the Atlantic, shower and thunderstorm activity will be possible each afternoon into the evening as the sea breeze pushes inland. By the weekend, there is an increased chance of showers and storms.

FOG POTENTIAL AND OTHER REMARKS: Patchy, shallow fog is possible Friday morning mainly over inland southeast GA.

CLIMATE

While record highs are not anticipated over the next several days despite the upward trend, the very mild low temperatures (lower to mid 70s) may result in some record warm minimums at Jacksonville and Gainesville. This may start as early as Friday and continue into early next week.

PRELIMINARY POINT TEMPS/POPS

AMG 69 90 70 89 / 20 60 60 90 SSI 76 87 76 87 / 0 20 20 40 JAX 73 91 73 91 / 0 40 10 50 SGJ 74 90 75 90 / 0 20 10 30 GNV 72 94 73 94 / 30 30 20 60 OCF 73 93 73 93 / 30 20 20 50

JAX WATCHES/WARNINGS/ADVISORIES

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