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

- Minor Tidal Flooding Continues for Portions of the St. Johns River Basin

- Minor River Flooding Continues Along Lower Portions of the Satilla River

- Patchy to Areas of Fog Possible at Inland Locations Early on Wednesday and Thursday mornings

- Increasing Coastal & Marine Hazards Saturday & Sunday. Gusty Onshore Winds Expected at Coastal Locations. High Risk of Rip Currents Likely at All Area Beaches

UPDATE

No significant changes to the forecast tonight as the forecast looks on track.

NEAR TERM /UNTIL 6 AM TUESDAY MORNING/

Main Highlights through Tonight:

- Minor Tidal Flooding Continues for Portions of the St. Johns River Basin in Putnam and western Flagler Counties.

Early afternoon surface analysis depicts strengthening high pressure (1022 millibars) building into the southeastern states in the wake of a frontal boundary that was stalling across south FL. Aloft...troughing was progressing eastward along the U.S. eastern seaboard, with ridging over the western Gulf and Deep South Texas building northward through the lower Mississippi Valley and the Ozarks. Latest GOES-East derived Total Precipitable Water imagery indicates that a seasonably dry air mass continues to advect into our region on the heels of breezy northwesterly low level flow, with PWATs ranging from around 0.6 inches over our western counties to around 0.9 inches across coastal southeast GA. Fair skies prevail throughout our region, with temperatures at 18Z rising through the lower and middle 80s area-wide, with dewpoints ranging from the mid 50s across portions of inland southeast GA to the low and mid 60s elsewhere.

Troughing aloft will shift further off the U.S. eastern seaboard tonight, allowing for stout ridging to expand into the southeastern states by Tuesday morning. Meanwhile, surface high pressure will slowly weaken overnight as it settles over the southern Appalachians and the Deep South. Low level flow will veer from northwesterly this afternoon to northerly this evening and then north-northeasterly during the predawn hours across our region. Our local pressure gradient will loosen by early this evening, allowing for winds to quickly decouple after sunset at most inland locations. A light northerly breeze at coastal locations this evening will shift to northwesterly overnight as drainage flow develops due to radiational cooling at inland locations. Some patchy radiation fog cannot be ruled out at inland locations towards sunrise, but the dry air mass in place across our area will likely keep coverage rather localized, and dense fog probabilities remain rather low at this time. Lows will fall to the upper 50s and lower 60s inland, ranging to the mid and upper 60s at coastal locations. These values are near or just slightly below mid-October climatology for our region.

SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/

Main Highlights This Period: Wednesday through Thursday night

- Dry weather with above average temperatures

A broad ridge of surface high pressure will prevail across the area this period, with an upper ridge overhead as well. Subsidence under the high pressure will result in dry weather this period, with mainly clear skies.

Temperatures will trend above average this period.

LONG TERM /THURSDAY THROUGH MONDAY/

Main Highlights This Period: Friday through Monday

- Coastal hazards including flooding, gusty winds, elevated rip risk expected from Friday night through Monday

High pressure will move east and weaken Friday, as a cold front approaches from the northwest. Precipitation chances will increase across north central FL as moisture pools ahead of the advancing front.

The cold front will move southeast across the area Friday night and Saturday, with strong high pressure building from the northwest. A surge of winds from the northeast will move down the coast following the frontal passage.

High pressure will build more toward the north then northeast Sunday into Monday. Elevated onshore winds will continue Sunday through Monday.

The greatest rainfall potential this period will be near the Atlantic coast, beginning Saturday afternoon and continuing through Monday.

AVIATION /00Z TUESDAY THROUGH 00Z WEDNESDAY/

VFR and mostly SKC through this period. The exception may be periods of IFR visibilities at VQQ during the predawn hours on Tuesday. Fair wx cumulus clouds looks likely for a time over parts of northeast FL Tuesday. For surface winds, they will diminish tonight with calm or light variable. Northerly sfc winds sustained around 5 knots will redevelop at the inland terminals by 14Z Tuesday, followed by winds shifting to northeasterly and increasing to 5-10 knots at the regional terminals.

MARINE

High pressure will settle over the southeastern states tonight, allowing winds and seas to subside early this evening. Onshore winds will develop on Tuesday as high pressure positions itself over the southern Appalachians, with winds and seas expected to remain below Caution levels through Friday evening. Winds will briefly shift to southerly and then southwesterly on Friday night ahead of a strong cold front that will approach our local waters from the northwest, with this front quickly moving southeastward across our area on Saturday morning. Northerly winds will abruptly increase following the passage of this front, with Small Craft Advisories likely and potential Gale Force wind gusts throughout the upcoming weekend as strong high pressure builds over the Ohio Valley and wedges down the southeastern seaboard. Winds will shift to northeasterly by Saturday evening, with increasing chances for showers across our local waters as the weekend progresses.

Rip Currents: Breezy offshore winds will keep the risk low at all area beaches today. Developing northeasterly winds will combine with an easterly ocean swell to create a lower end moderate risk at the northeast FL beaches from Tuesday through Thursday, while low surf heights keep the risk generally low at the southeast GA beaches.

FIRE WEATHER

Dry weather is expected through at least Thursday. Surface and transport winds will shift to northeasterly towards sunrise on Tuesday, with breezy surface speeds expected along the northeast Florida coast on Tuesday afternoon. Lighter transport speeds across southeast Georgia will yield generally fair daytime dispersion values on Tuesday, while good values continue for inland locations in northeast and north central Florida. Surface and transport winds will shift slightly to east-northeasterly by Wednesday, with fair to good daytime dispersion values continuing at inland locations, while poor values are expected for coastal southeast Georgia.

FOG POTENTIAL AND OTHER WEATHER REMARKS: Patchy fog formation is possible at inland locations during the predawn and early morning hours on Wednesday and Thursday.

HYDROLOGY

Minor flooding will continue along lower portions of the Satilla River during the next several days. Water levels have fallen below flood stage along portions of the St. Mary's River near the gauge at Macclenny, where river flood warnings have been recently discontinued.

TIDES/COASTAL FLOODING

Minor tidal flooding is now confined to the St. Johns River and its tributaries in Putnam County, as well as along Crescent Lake in western Flagler County. Elevated astronomical tides and north to northeasterly winds developing on Tuesday may keep water levels elevated to around 1.5 - 2 feet above normally dry ground during times of high tide through around midweek.

PRELIMINARY POINT TEMPS/POPS

AMG 58 86 61 86 / 0 0 0 0 SSI 66 82 68 82 / 0 0 0 0 JAX 62 85 65 85 / 0 0 0 0 SGJ 67 83 68 84 / 0 0 0 0 GNV 61 87 64 86 / 0 0 0 0 OCF 62 86 64 86 / 0 0 0 10

JAX WATCHES/WARNINGS/ADVISORIES

FL...Coastal Flood Advisory until 7 AM EDT Tuesday for FLZ038-137. GA...None. MARINE...None.