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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

- Coastal Flood Warnings Remain in Effect through Thursday Night along the coast, the Intracoastal Waterway, and the Entirety of the St. Johns River basin.

- Coastal and Marine Hazards Continue into the Upcoming Weekend. Extended Duration of Moderate Tidal Flooding within the St. Johns River Basin Continues into the Upcoming Weekend. High Surf Advisory through Thursday Night at the Northeast FL Beaches. High Risk for Rip Currents at all Area Beaches through the Upcoming Weekend. Major Beach Erosion around Times of High Tide through Friday. Small Craft Advisory for the Atlantic Waters through at least Friday. Gusty Northeasterly Winds Continue at Coastal Locations through Friday.

- Isolated Thunderstorms Possible on Sunday and Sunday Night

NEAR TERM /THROUGH TONIGHT/

Main Highlights:

- Coastal Flood Warnings Re-Issued for Coastal Glynn and Camden Counties through Thursday Night.

- Coastal Flood Warnings Remain in Effect through Thursday Night along Coastal Northeast FL, the Intracoastal Waterway, and the Entirety of the St. Johns River basin.

- Coastal and Marine Hazards Continue into the Upcoming Weekend. Extended Duration of Moderate Tidal Flooding within the St. Johns River Basin Continues into the Upcoming Weekend. High Surf Advisory through Thursday Night at the Northeast FL Beaches. High Risk for Rip Currents at all Area Beaches through the Upcoming Weekend. Major Beach Erosion around Times of High Tide through Friday. Small Craft Advisory for the Atlantic Waters through at least Friday. Gusty Northeasterly Winds Continue at Coastal Locations through Friday.

Early morning surface analysis depicts strong high pressure (1035 millibars) centered over New England, with this feature wedging down the southeastern seaboard, with sharp coastal troughing prevailing over the near shore Atlantic waters adjacent to coastal southeast GA and northeast FL. Meanwhile, weak low pressure has developed near the southeast FL coast along a surface trough axis that extends across the northwestern Bahamas. Aloft...a highly amplified pattern persists across our region, as ridging continues to build from the Gulf northeastward along the southeastern seaboard, with this feature deflecting a shortwave trough northeastward across the Great Lakes region. A stubborn cutoff trough otherwise remains in place near the northwestern Bahamas. Latest GOES-East derived Total Precipitable Water imagery indicates that a seasonably dry air mass prevails for locations north of Waycross in southeast GA, where PWATs were below 0.5 inches. PWATs elsewhere ranged from around 0.75 to 1 inch across the rest of our area, while deeper moisture, featuring PWATs in excess of 1.5 inches, was located south of the I- 4 corridor in central FL. Pockets of lower stratus and stratocumulus cloud cover were located across portions of northeast and north central FL, while fair skies prevailed across most of southeast GA. Breezy northeasterly winds were keeping temperatures at coastal locations generally in the upper 60s to mid 70s as of 08Z, while lighter northerly winds elsewhere have allowed temperatures to fall to the mid 50s across portions of inland southeast GA to the low and mid 60s for inland locations in northeast and north central FL.

Strong high pressure will continue to wedge down the southeastern seaboard through tonight as it shifts offshore of coastal New England by this afternoon and evening. Sharp coastal troughing will remain in place to the south of this feature across our near shore Atlantic waters, and weak low pressure will remain situated near coastal southeast FL through tonight. The combination of these features will keep a tight local pressure gradient in place across our region, with northeasterly winds potentially approaching Wind Advisory criteria this afternoon at area beaches. Isentropic lift associated with the surface trough axis situated from south FL east- northeastward across the northwestern Bahamas will strengthen from south to north this afternoon and evening as increasing PWATs lift northward from the FL peninsula. Marine stratocumulus will continue to occasionally move onshore today in the gusty northeast flow for coastal northeast FL, with shower coverage increasing towards sunset for locations south of St. Augustine. A lingering dry air mass elsewhere and plenty of sunshine this morning will allow highs to climb to near 80 for inland locations along and west of the U.S. Highway 301 corridor. Breezy to windy conditions developing this afternoon for locations along and east of I-95 will keep highs in the mid to upper 70s.

Isentropic lift will continue to strengthen from south to north tonight, with coastal troughing generating scattered to numerous showers over the Atlantic waters that will advect onshore across coastal northeast FL, with widely scattered showers pushing inland past the U.S. Highway 301 corridor after midnight. Increasing cloud cover and continued breezy northeast winds will keep lows in the upper 60s and lower 70s for locations south of the Interstate 10 corridor, while fair skies allow lows for inland locations north of I-10 to fall to the low and mid 60s.

SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/

Main Highlights This Period:

- Coastal Flooding Hazards Continue: Minor to Moderate Flooding During Times of High Tide Along the Atlantic Coast and Within the Intracoastal Waterway and the Entirety of the St. Johns River Basin.

- Beach Hazards Continue: High Surf Advisories Continuing at the Northeast FL Beaches, High Risk for Deadly Rip Currents At All Area Beaches. Moderate to Major Beach Erosion Continues.

Though there will be some slight changes to the pattern by the Thursday/Friday time frame, the general sentiment and forecast will be mostly the same story as onshore flow pattern continues. The primary change will be the upper low/surface troughing over the Bahamas starting to weaken and drift towards the northeast away from the region Thursday Night and Friday. This however will not affect the onshore flow pattern very much, as a "re-inforcing" ridge of high pressure will build across the southeastern states once again during the Thursday Night to Friday time frame. In the end, this will persist a breezy 10-20G25-35mph type of wind during most of the short term period, generally highest closer to the coast and across the northeast FL St. Johns River basin, isolated to scattered showers near the coast and portions of northeast FL, and temperatures generally in the mid 70s by the coast to the low to mid 80s inland with less cloud cover.

Coastal Hazards: Persistent onshore flow, combined with elevated astronomical tides lingering with the full moon earlier this week, will sustain widespread minor to moderate tidal flooding along the Atlantic coast, Intracoastal Waterway, and St. Johns River basin through Thursday night. Coastal Flood Warnings remain in effect for the entirety of the coast and St. Johns River. Hazardous surf and a High Risk of Rip Currents will persist at area beaches, with significant beach erosion likely around times of high tide. A High Surf Advisory remains in effect for northeast FL beaches through Thursday.

LONG TERM /SATURDAY THROUGH TUESDAY/

Main Highlights This Period:

- At Least Minor Tidal Flooding Likely to Continues During Times of High Tide Within the St. Johns River Basin

- Elevated Rip Current Risk, Surf Likely Continuing through the Upcoming Weekend

- Increasing Chances Thunderstorms on Sunday and Sunday Evening

The overall pattern will evolve through the weekend, introducing heightened possibilities for showers and thunderstorms by Sunday as a frontal boundary and associated upper trough moves into the southeastern states. Onshore flow will be generally unchanged through Saturday before winds veer more southeasterly Saturday Night and Sunday ahead of the approaching boundary. Depending on the exact timing of the front as well as behavior of the associated upper low (in which long term guidance has modest differences), this will determine the extent of thunderstorm potential on Sunday & Sunday Night, as well as any strong to severe storm threat. Monday and Tuesday look to be a mostly dry "transition" days before another frontal boundary approaches by Wednesday.

As mentioned above, elevated coastal water levels and hazardous beach conditions may persist into the weekend as the prolonged onshore flow gradually weakens. Tidal flooding will remain a concern, particularly within the St. Johns River basin where "trapped" tides may take longer to recede. Rough surf and an elevated rip current risk will likely continue along area beaches as well. The change in pattern however should at least abate most of these hazards with the changes in wind direction, except for some areas where locally very heavy rainfall occurs.

Regarding temperatures, they will trend near or slightly above climo as the pattern/wind direction shifts frequently.

AVIATION /12Z WEDNESDAY THROUGH 12Z THURSDAY/

MVFR ceilings will filter across the northeast FL terminals towards 18Z, with isolated showers possible after 23Z. Kept vicinity coverage of showers at the Duval County terminals and GNV at this time. North-northeasterly surface winds will become gusty towards 14Z, with sustained speeds increasing to 15-20 knots at SGJ and CRG and 10-15 knots elsewhere, followed by speeds increasing to around 20 knots at SGJ, CRG, SSI and JAX after 18Z, while speeds at GNV and VQQ increase to around 15 knots. Surface speeds will only slowly subside after 23Z.

MARINE

Strong high pressure situated over New England will continue to wedge down the southeastern seaboard as it slowly shifts offshore this afternoon. Meanwhile, weak low pressure situated near southeast Florida will meander through Thursday before dissipating on Thursday night and Friday. These two features will create gusty northeasterly winds through Friday, keeping Small Craft Advisory conditions in place throughout our local waters. Coastal troughing situated over our near shore waters will remain in place through Saturday, with this feature generating scattered to numerous showers this afternoon for the waters from around St. Augustine southward, with this activity then overspreading most of our local waters tonight. Periods of isolated to widely scattered showers will then be possible from Thursday through Sunday morning. Another strong high pressure center building southeastward from New England and the Mid- Atlantic states this weekend will result in breezy easterly winds across our local waters, with another round of Small Craft Advisory conditions possible as seas build. A disturbance aloft moving across our area on Sunday and Monday may generate numerous showers and a few embedded thunderstorms.

Rip Currents / High Surf: High Surf Advisories remain in effect for the northeast FL beaches through Thursday night, where breakers of 6 to 9 feet will prevail. Breakers of 3 to 6 feet will prevail at the southeast GA beaches through Thursday. These elevated, rough surf conditions will maintain a high risk of deadly rip currents at all area beaches through the upcoming weekend, and major beach erosion is likely to occur around times of high tide during this extended duration onshore wind event.

FIRE WEATHER

AREAS OF ELEVATED NIGHTTIME DISPERSIONS AT COASTAL LOCATIONS - Through Thursday Night

Persistent east to northeast onshore flow will persist through the rest of the week, though will weaken slightly by Thursday/Friday. This will not change expected conditions much however, as showers will continue to occasionally move onshore across mainly northeast FL with poor to fair coastal dispersions, in the fair to good range inland with better mixing. Areas of high nighttime dispersion will also continue near the coast through at least Thursday Night. The pattern changes this weekend as a cold front approaches from the northwest, which will return chances for higher coverage of showers and thunderstorms this weekend.

FOG POTENTIAL AND OTHER WEATHER REMARKS: Significant fog formation is not expected during the next several days.

TIDES/COASTAL FLOODING

Northeasterly winds will remain breezy to windy and will combine with high astronomical tides due today's lunar perigee to maintain moderate tidal flooding through Thursday along our local Atlantic coast and within the Intracoastal Waterway (ICWW) and the entirety of the St. Johns River basin. Water levels will generally reach 2-3 feet above Mean Higher High Water (MHHW) during times of high tide through Thursday. Coastal Flood Warnings have been re-issued for coastal Camden and Glynn Counties in southeast GA, with Coastal Flood Warnings continuing along our Atlantic coast and within the ICWW and St. Johns River basin through Thursday night. Moderate tidal flooding may linger into the upcoming weekend within the St. Johns River basin, with minor flooding potential continuing around times of high tide along the Atlantic coast and within the St. Johns River The long duration of this strong onshore wind event will likely produce major beach erosion during each high tide cycle through at least Thursday.

PRELIMINARY POINT TEMPS/POPS

AMG 80 62 81 59 / 0 10 0 0 SSI 75 66 75 63 / 10 10 10 0 JAX 77 67 78 66 / 10 30 10 0 SGJ 77 72 78 69 / 40 70 50 20 GNV 80 69 82 67 / 10 20 10 0 OCF 80 70 83 68 / 10 20 30 0

JAX WATCHES/WARNINGS/ADVISORIES

FL...Coastal Flood Warning until 2 AM EDT Friday for FLZ038-124-125- 132-137-138-225-233-325-333-633. High Risk for Rip Currents through Friday evening for FLZ124-125- 138-233-333. High Surf Advisory until 2 AM EDT Friday for FLZ124-125-138- 233-333. GA...Coastal Flood Warning until 2 AM EDT Friday for GAZ154-166. High Risk for Rip Currents through Friday evening for GAZ154-166. MARINE...Small Craft Advisory until 6 AM EDT Friday for AMZ450-452-454- 470-472-474.