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

- Locally Dense Fog Possible for Inland SE GA and Suwannee Valley this morning, and again Friday morning

- Rain and afternoon thunderstorm chances increase today through the weekend.

- Local Nor'easter Conditions likely Next Week

- Moderate Risk of Rip Currents Continues at All Area Beaches

NEAR TERM /THROUGH TONIGHT/

Main Highlights Today and Tonight:

- Isolated Strong Thunderstorms with Locally Heavy Rainfall Possible this afternoon/evening for Inland Northeast Florida.

- Late night/early morning patchy dense fog inland SE GA/Suwannee Valley of inland North Florida.

Southeast steering flow will continue to slowly moisten the atmosphere with PWATs reaching close to 2 inches across NE FL later today. This pattern combined with diurnal heating and inland moving sea breeze fronts will trigger numerous showers and scattered storms across NE FL and scattered showers and isolated storms across SE GA. A few of the storms will be strong across inland NE FL with gusty winds to 40 mph and the main threat of locally heavy rainfall. Max temps will continue at above normal levels with highs around 90F inland, upper 80s along the I-95 corridor and middle 80s along the Atlantic Coast. Inland storms should fade around sunset this evening with focus shifting to the Atlantic Coastal waters where scattered showers and isolated storms will set up overnight, with a few showers making it to the NE FL coastal areas towards morning. Above normal temps will continue with lows in the upper 60s/near 70F inland SE GA, lower 70s inland NE FL and middle 70s along the Atlantic Coast. Low level moisture and mostly clear skies during the overnight and early morning hours will support patchy dense fog across inland SE GA and along the I-10 corridor west of JAX through the Suwannee Valley of inland North FL. Dense fog potential not as high as last night, with only 20-30% chance of Dense fog advisories along the Altamaha and Ocmulgee River basins around sunrise Thursday.

SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/

Main Highlights:

- Above normal rain chances through the weekend. Localized heavy downpours and flooding possible.

Deep southeasterly flow will saturate the column to end the work week. A cloudy start Friday is possible as remnant convective cloud cover and a embedded shortwave track northwestward out of southern FL. Warm air aloft will keep lapse rates and elevated instability rather weak but there should be enough diurnal instability to support scattered to numerous showers with isolated thunderstorms during the afternoon hours Friday. The main concerns will be some possible training showers along the sea breeze given the southerly steering flow and heavy downpours in general with tropical-like rain rates leading to isolated pockets of heavy rain. The Atlantic sea breeze is progged to track well inland and take convection with it as it exits west beyond the I-75 corridor during the early evening Friday.

A similar pattern is likely pan out on Saturday and Sunday as mean upper ridging remains anchored across FL before breaking down in advance of an upstream trough Sunday night. Unsettled weather fueled by recycled moisture will continue potential for numerous heavy downpours and compounding rainfall through the weekend, but warm temperatures aloft again will limit the potential for high thunderstorm coverage and potential for significant thunderstorm impacts. Steering flow will transition southerly and eventually southwesterly through Sunday which will lead to high rain chances across inland areas, favoring counties between the I-75 and I-95 corridors through the early evening.

As the incoming trough approaches Sunday night, a line of thunderstorms may develop to the west and approach inland SE GA during the overnight hours Sunday night into Monday morning. If timing holds, the dynamics (trough amplification) and instability do not appear sufficient to support strong nocturnal thunderstorms but we will continue to monitor this potential. At this time, anticipate mostly rain with embedded thunder focused across SE GA through the predawn hours Monday.

Warm and humid conditions will continue through the weekend ahead of the approaching frontal system; highs are expected to read in the mid to upper 80s with overnight lows in the low/mid 70s.

LONG TERM /MONDAY THROUGH WEDNESDAY/

Main Highlights This Period:

- Local Nor'easter Conditions Next Week

- Minor to Moderate Tidal Flooding, Deadly Surf, and Gusty Coastal Conditions.

- Potential for several days of excessive rainfall somewhere along the local coast Monday through Wednesday.

Though there's still a substantial degree of uncertainty next week, as another local nor'easter develops a cold frontal passage Monday night. Moderate nor'easter conditions are likely, including strong gusts (possibly Wind Advisory levels of 40-45 mph) at the coast, rounds of heavy rain, dangerous surf conditions, minor to moderate beach erosion, and tidal flooding at the Atlantic coast and within the St Johns River.

Tidal flooding is likely to be a multi-day concern as the astronomical tides begin increasing next week as the New Moon approaches. Minor to possible low-end Moderate tidal flooding will be possible potentially into next weekend

The lower forecast confidence revolves around the potential for excessive rainfall especially at the coast. It comes down to two scenarios: (1) the front stalls and convergence near the FL/GA state line, leading to several days of heavy rainfall, possibly up to 4- 8"; or (2) a slightly more progressive front sinks farther south into central FL keeping the heavier precip potential south of the local area. Right now, guidance has trended closer to scenario (2) but please keep a close eye on this as it may exacerbate the "high confidence" tidal flooding.

Temperatures will be on the cooler side due to the frontal position and heavy cloud cover and precip potential over the area. Expect highs to tumble to the 70s with fairly minimal diurnal ranges on the warm side of the front. On the cooler side, which is most likely to be SE GA, the overnight lows may dip into the upper 50s once again.

AVIATION /06Z THURSDAY THROUGH 06Z FRIDAY/

VFR conditions expected to prevail but MVFR to IFR visibilities likely developing at VQQ towards 08Z, with periods of LIFR conditions expected through around 12Z. A few showers may impact SGJ late tonight and Thu morning. Confidence was too low to indicate anything other than vicinity showers at SGJ at this time for Thu morning. East to southeasterly winds will then increase to 10 knots by 15Z-18Z Thu at the regional terminals. Rain/Isolated Storm chances slightly higher for Thu afternoon and will include TEMPO groups at GNV and PROB30 groups at JAX/VQQ for TSRA activity and potential MVFR conds, mainly from 18-22Z time frame.

MARINE

High pressure over the Carolinas will move offshore and winds turn more east and southeast with rain chances gradually increasing through the weekend as another front settles over the southeast states. By early next week, strong high pressure over the eastern U.S. and the Mid Atlantic States will wedge down the east coast, bringing a cold front through the area waters Monday and result in strengthening northeast winds and building seas. Small Craft Advisory headlines are likely early next week with potential for wind gusts to gale force.

Rip Currents: A combination of long period east swells near 1-2 ft, onshore flow, and prior surf conditions suggest a low-end moderate risk of rip currents through Friday.

FIRE WEATHER

Increasing moisture and high rainfall chances return through the rest of the week and into next as "backdoor" cold front stalls across the region. Today, prevailing surface and transport winds from the east-southeast will favor a progressive Atlantic sea breeze and fair afternoon smoke dispersion inland. Scattered thunderstorms will be possible across NE FL with only an isolated potential for SE GA. Through the weekend, winds will turn southeasterly Friday and Saturday before shifting southerly ahead on the incoming cold front on Sunday. Stronger and gusty northeasterly winds are expected to develop Monday and continue through at least Thursday. Though daytime dispersions will kept in check by lower mixing heights and cloud cover, the overnight dispersions may reach "high" levels for one or two nights next week.

Fog Potential...Patchy fog over inland southeast Georgia and portions of the Suwannee Valley this morning and again Friday. Erratic and gusty outflow winds will be possible in the vicinity of thunderstorms.

EQUIPMENT

The KVAX Doppler Radar in Valdosta GA near Moody AFB remains out of service until further notice. Please utilize KTLH (Tallahassee), KJGX (Robins AFB), or KJAX (Jacksonville) during the outage period.

PRELIMINARY POINT TEMPS/POPS

AMG 90 70 90 72 / 30 10 60 50 SSI 85 75 86 74 / 20 10 60 50 JAX 88 73 88 72 / 50 20 70 40 SGJ 87 75 87 74 / 40 30 60 30 GNV 90 72 89 71 / 70 30 70 50 OCF 91 72 90 73 / 70 40 70 50

JAX WATCHES/WARNINGS/ADVISORIES

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