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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 Showers and Isolated Thunderstorms Today. Heavy Downpours Possible Along the Interstate 95 Corridor through Thursday

- Strengthening Onshore Winds & Increasing Marine Hazards through Saturday.

- High Risk for Rip Currents and Increasingly Rough Surf at All Area Beaches.

- Frequent Wind Gusts of 35-45 mph Possible at Coastal Locations on Thursday.

- Small Craft Advisories through at least Friday Night for All Atlantic Coastal Waters. High Surf Advisories Possible Along the Northeast FL Coast from Thurs - Sat.

- Minor Coastal Flooding Around Times of High Tide from Thursday Evening. Minor Tidal Flooding Around Times of High Tide within the St. Johns River Basin

UPDATE

Earlier Isolated to widely scattered showers have ended inland with a couple brief showers over the Suwannee Valley that will end soon. Widely scattered coastal showers over the northeast FL waters will continue overnight with an isolated T'storms offshore and a few showers moving onshore the NE FL coast overnight.

Breezy winds 10-15 mph gusting to 25 mph will continue along the coast overnight turning northerly and lightning to 8-12 mph inland as the cold front sinks further south into NE FL and low stratus sinks southward following the front into SE GA through midnight and then sinking into NE FL after midnight. Elevated winds will prevent fog.

NEAR TERM /THROUGH THURSDAY/

nbhMain Highlights through Tonight:

- Isolated storms with gusty showers capable of locally heavy rain

- Breezy onshore winds and dangerous rip current/surf conditions

A cold front, driven by strong northeasterly winds between moderately strong surface ridge wedging southward along the eastern seaboard and a low positioned well off the Mid Atlantic coast.

Gusty northeasterly flow has pushed into the SE GA this morning with the front steadily progressing through NE FL this afternoon, eventually slowing across central FL tonight. With the stronger coastal winds, scattered to numerous showers and isolated t'storms will push onshore throughout the afternoon with fast-moving but heavy downpours. Best chances for a few isolated thunderstorms this afternoon will be mainly across north-central FL where modest diurnal instability will build through the early afternoon hours. Over southeast GA, drier conditions prevail.

Due to a slightly faster frontal intrusion, temperatures and cloud cover will limit today's highs in SE GA to low 80s, while on the warm side of the boundary temperatures rise to the mid/upper 80s, except at the coast where onshore winds will keep highs also in the low 80s.

Drier on its way will not arrive until late tonight, with the drier, cooler airmass arriving tomorrow. Winds will taper off after midnight, especially inland, and allow low temperatures to reach the upper 60s across SE GA tonight while another night of min temps in the low/mid 70s is expected across NE FL and along the coast.

SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/

Main Highlights This Period:

- Increased Marine and Coastal Impacts for Thursday through Friday

- Cooler and Drier Conditions for the End of the Week

- Minor Coastal Flooding Likely During High Tide along the Coast and the St Johns River Basin

Cool dry air associated with high pressure to the north will press down over the forecast area bringing dry weather, cooler temperatures, and clearing skies for the end of the week. Breezy northerly-northeasterly winds will continue through Thursday and into Friday due to the tightened pressure gradient, resulting in a continuation for increased risk for rip currents along area beaches with a potential for tidal flooding for coastal areas and portions of the St Johns River on Friday. High temperatures by the end of the week will be in the upper 70s and lower 80s with overnight low temperatures dropping down into the mid to upper 50s over southeast Georgia and in the upper 50s and lower 60s for northeast Florida, with min temps in the mid to upper 60s along the coastline.

LONG TERM /SUNDAY THROUGH WEDNESDAY/

Main Highlights This Period:

- Marine and Coastal Impacts Subside after Saturday

- Temperatures will Warm through Early Next Week.

- Minor Coastal Flooding Likely Around Times of High Tide Along the Atlantic Coast through Saturday. Minor Tidal Flooding Possible within the St. Johns River Basin this Weekend and Early Next Week.

Dry weather conditions will continue through Saturday & Sunday and on into Monday, with winds lessening over the weekend as the pressure gradient laxes over the region and the influence of high pressure to the north lessens and withdraws before midweek. Chances for convection will increase by Tuesday, primarily for north central Florida and for areas along the coast as prevailing flow shifts to become more out of the south. Temperatures will experience a warning trend through the weekend and into the beginning of next week, rising to be above the seasonal average by the end of the period with max temps rising into the upper 80s and lower 90s.

AVIATION /00Z THURSDAY THROUGH 00Z FRIDAY/

A mix of VFR and MVFR ceilings will continue through 06Z as northeasterly elevated onshore flow brings in low level moisture with isolated to widely scattered coastal showers on occasion moving onshore at SGJ and CRG, but staying dry inland. Ceilings will lower to MVFR from northeast to southwest overnight as a cold front moves southward through the area with stratus clouds lowering the ceilings to 1.0 kft to 2.0 kft by 06Z and to IFR levels below 1.0 kft at SSI after 06Z, persisting there into midday Thursday. Northeast winds will back northerly and remain near 10 knots inland and 10-15 knots along the coast with gusts to 20 knots will continue at SSI, SGJ, and CRG, and

Winds will increase after 12-14Z as strong high pressure ridging builds south along the southeast US coast as the strong pressure gradient and some mixing both lifts ceilings to 2.0-2.5 kft and brings north to northeasterly winds 15-20 knots with gusts to 25-30 knots at SSI and SGJ and near 15 knots gusting to 25 knots at JAX, VQQ, and GNV. Ceilings at SSI will lower to IFR levels near the end of the period as low stratus resettles in from the Atlantic in the onshore flow. Have a Prob30 group for convergent coastal showers intruding at SGJ after 18Z Thursday. VFR ceilings expected at GNV after 18Z Thursday as some drier air arrives from the north inland and scatters clouds near 2.5 kft.

MARINE

Low pressure will strengthen well to the northeast of the region through the end of the week, tracking further to the north of the area through the weekend. High pressure will build down the eastern US coastal states Wednesday causing a backdoor cold front to sweep southward. The gradient between the high, and the front trailing from the low to the northeast, will result in enhanced northeasterly winds and waves beginning later today and lasting through at least Friday. A prolonged period of Small Craft conditions will continue through at least Friday night. There is also the potential for Gale conditions Thursday into Thursday night with at least occasional gusts to Gale force. These conditions ease this weekend as high pressure weakens and the aforementioned low pulls further away from the area.

Rip Currents: There will be several days of strong and dangerous rip currents with as elevated risk through the upcoming weekend. Additionally, strong northeasterly winds will increase breakers to 5- 8 feet through Thursday afternoon, increasing the surf danger.

FIRE WEATHER

Scattered to numerous showers will spread south and westward across most of northeast and north central FL by this afternoon. Shower activity will then shift to the Interstate 95 corridor tonight through Thursday evening before a drier air mass overspreads our entire area from Friday through Monday. This drier air mass will drop minimum humidity values to near critical thresholds across inland portions of southeast Georgia by Sunday afternoon.

Northeasterly transport winds will gradually strengthen from north to south today, with breezy surface winds spreading inland this afternoon. These strengthening winds will create fair to good daytime dispersion values. North-northeasterly surface and transport winds will remain breezy at coastal locations tonight, creating elevated nighttime dispersion values. North-northeasterly surface and transport winds will continue to strengthen on Thursday and Thursday night along the I-95, with breezy conditions redeveloping at inland locations by mid-morning Abundant lower cloud cover will keep daytime dispersion values in the fair to good range despite breezy to windy conditions. Elevated nighttime dispersion values are forecast to continue along the I-95 corridor on Thursday night due to breezy surface speeds. Breezy northerly surface and transport winds and decreasing cloud cover on Friday at inland locations will create good daytime dispersion values area-wide.

Fog Potential...Significant fog formation is not expected during the next several days.

TIDES/COASTAL FLOODING

Astronomical tides will rise through the weekend due to the upcoming Full "Harvest" Moon that occurs on Saturday. A northeast wind surge will overspread coastal locations through Thursday will combine with the increasing astronomical tides to create minor coastal flooding along the Atlantic coast from Thursday evening through at least Saturday. Minor flooding will be possible along the Atlantic coast beginning with the evening high tide on Thursday, where water levels of 1.5 - 2.5 feet above Mean Higher High Water (MHHW) are preliminarily forecast, which will create mostly minor, nuisance type flood impacts. Minor flooding will then expand to the St. Johns River basin beginning on Friday and are expected around times of high tide through the weekend and into next week, as rising astronomical tides beyond the date of the Full Moon keep water levels elevated, generally at 1-2 feet above MHHW during each tide cycle for most locations within the basin.

PRELIMINARY POINT TEMPS/POPS

AMG 68 81 61 79 / 10 0 0 0 SSI 73 81 66 79 / 40 10 10 0 JAX 72 82 66 80 / 40 10 20 0 SGJ 75 82 71 79 / 50 50 40 10 GNV 71 86 66 83 / 10 10 10 0 OCF 73 88 68 85 / 10 10 0 0

JAX WATCHES/WARNINGS/ADVISORIES

FL...High Risk for Rip Currents through late Saturday night for FLZ124- 125-138-233-333. Coastal Flood Advisory from 5 PM Thursday to 11 AM EDT Friday for FLZ124-125-138-225-233-325-333. GA...High Risk for Rip Currents through late Saturday night for GAZ154- 166. Coastal Flood Advisory from 5 PM Thursday to 11 AM EDT Friday for GAZ154-166. MARINE...Small Craft Advisory until 8 PM EDT Friday for AMZ450-470. Small Craft Advisory until 2 AM EDT Saturday for AMZ452-454- 472-474.