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

- Gusty Southwest Winds this Afternoon Increase the Wildfire Danger. Sustained Speeds of 15-20 mph with Frequent Gusts of 25-30 mph are Forecast.

- Moderate to Heavy Showers Late Tonight through Saturday. A Few Strong Storms are Possible Across Southeast GA on Friday. Rainfall Amounts of 0.5 to 2 Inches are Forecast, with Locally Higher Totals Possible.

- Moderate Risk of Rip Currents at All Area Beaches.

- Extended Period of Breezy Onshore Winds Expected Next Week. Increasing Marine Hazards Likely by Tuesday and Wednesday.

NEAR TERM /THROUGH TONIGHT/

Overnight surface analysis depicts Atlantic high pressure that was extending its axis westward across the FL peninsula. Meanwhile, a wavy frontal boundary extends from the Mid-Atlantic states westward across the Ohio and Missouri Valleys and through the Southern Plains states. Aloft...zonal flow prevails across the southeastern states, downstream of a shortwave trough that was digging southeastward across the Plains states. Thin cirrus continues to blanket our area, with stratocumulus clouds beginning to increase for locations near the Altamaha River in southeast GA. Low level south-southwesterly flow was providing warm air advection for locations along and north of the Interstate 10 corridor, where temperatures were generally in the 50-55 degree range at 06Z. Closer to the ridge axis, a drier air mass across north central FL will fall to the 40-45 degree range. Dewpoints ranged from the upper 30s across portions of north central FL to the 45-50 range elsewhere.

Shortwave troughing will migrate quickly east-southeastward from the Plains states through the Missouri and Tennessee Valleys today, carving out a broad longwave trough over the lower Mississippi Valley by early Friday. This developing trough will drive a slow moving frontal boundary into the southeastern states tonight. Our local pressure gradient will tighten downstream of this approaching front today as Atlantic surface ridging only slowly loosening its grip on the FL peninsula. Gusty southwesterly winds will gradually increase low level moisture levels for inland portions of southeast GA and western portions of the Suwannee Valley, with PWATs climbing above 1 inch before noon today and then above 1.25 inches by sunset. Isolated to widely scattered, mainly light showers will be possible for locations north and west of Waycross, mainly this afternoon and evening.

A low level dry air mass will otherwise be slow to scour out over north central FL, and strengthening southwesterly wind speeds of 15-25 mph are expected by early afternoon, with occasional gusts up to 30 mph possible through the mid to late afternoon hours. Although humidity values should remain above critical thresholds, breezy and gusty winds all afternoon will combine with ongoing extreme drought conditions to create dangerous wildfire conditions across northeast and north central FL as well as for locations south and east of Waycross in southeast GA. Warm air advection will boost highs to the mid to upper 70s at most locations, except around 70 for coastal southeast GA.

Deeper moisture will pool across central portions of AL and GA this evening ahead of the approaching frontal boundary, with some elevated instability crossing the Ocmulgee and Altamaha Rivers towards sunrise on Friday. A wide band of moderate to occasionally heavy showers will sink southward across southeast GA during the predawn and early morning hours on Friday, with isolated embedded (and elevated) thunderstorms possible towards sunrise. Otherwise, deepening west-southwesterly flow ahead of the approaching front may increase moisture levels enough for some fog and lower stratus cloud cover to advect onshore from Apalachee Bay and the northeast Gulf across southern portions of the Suwannee Valley, north central FL, and southern portions of the St. Johns River basin after midnight through the predawn hours on Friday. Increasing cloud cover and warm air advection will otherwise keep lows in the 55-60 degree range area-wide.

SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/

Main Highlights During the Period:

- Shower and thunderstorm chances through Saturday, with a few strong storms possible.

Frontal boundary will lay southwest to northeast, just north of forecast area Friday morning. The boundary will sink south across SE GA during the day Friday. Showers, with embedded thunderstorms are expected to move northeast along the boundary throughout the day over SE GA. Much of the day Friday will be dry over NE FL, with best chances in the afternoon. The boundary will sink into NE FL Friday night, with the greatest chances for convection shifting with the boundary.

The boundary will push to the south Saturday afternoon, as high pressure builds from the north. Most of Saturday will dry across SE GA, especially in the afternoon hours.

Rainfall amounts will vary across the region. At this time the highest amounts are expected over SE GA on Friday, when best lift along the front will be present.

Temperatures will trend above normal Friday and Friday night, then near normal for Saturday and Saturday night.

LONG TERM /SUNDAY THROUGH WEDNESDAY/

Main Highlights During the Period:

- Mainly coastal showers next week.

High pressure will be centered to the north Sunday through Wednesday. An inverted trough is expected to develop along the coastal waters Tuesday and linger through Wednesday. This trough will provide the chance for mainly coastal showers Tuesday and Wednesday.

Temperatures will trend above normal this period.

AVIATION /12Z THURSDAY THROUGH 12Z FRIDAY/

VFR conditions will prevail. Scattered showers may approach the regional terminals towards the end of this TAF period, or around 12Z Friday. Broken ceilings of 5,000 - 6,000 feet will be possible at the regional terminals, mainly after 15Z. Otherwise, south to southwesterly surface winds sustained around 5 knots early this morning will increase to around 15 knots by 17Z, with frequent gusts of 20-25 knots expected through around 22Z. Speeds will then diminish to 5-10 knots towards 00Z Friday.

MARINE

High pressure centered offshore of the southeastern seaboard will continue to extend its axis westward across the Florida peninsula through Thursday, maintaining breezy south- southwesterly winds today for the offshore waters. Meanwhile, a frontal boundary stretching across the Ohio and Tennessee Valleys will push into the southeastern states on Thursday night. Showers and thunderstorms will increase in coverage across our local waters from late Thursday night through Saturday as the front slowly moves across our area. Activity will then exit the northeast Florida waters on Saturday night as the frontal boundary shifts southward over the Florida peninsula.

High pressure building over the southeastern states in the wake of this frontal passage will create a prevailing north- northeasterly wind flow this weekend. An extended period of breezy onshore winds are then expected next week as a series of strong high pressure centers migrate eastward across New England the offshore of the U.S. eastern seaboard, with these features wedging down the southeastern seaboard. Coastal troughing developing over our local waters early next week will generate rounds of scattered showers and possibly a few embedded thunderstorms.

Rip Currents: A long period east-northeasterly ocean swell will persist today before fading overnight, keeping a moderate risk in place at all area beaches. A low risk is then expected on Friday and Saturday due to light winds and lower swell periods, with a moderate risk returning by Sunday and Monday due to gradually strengthening onshore winds that will continue through all of next week.

FIRE WEATHER

- Areas Of High Dispersions Today - Areas Of Low Dispersions Se Ga Friday - Areas Of High Dispersions Ne Fl Friday - Areas Of Low Dispersions Saturday - Patchy High Dispersions Monday And Wednesday - Areas Of High Dispersions Tuesday

High pressure will move away to the east Today. A frontal zone will slowly move south across the region Tonight through Saturday. High pressure will become centered to the north Sunday through Thursday.

FOG POTENTIAL AND OTHER REMARKS: Significant fog is not expected this morning. Thunderstorms are in the forecast for Tonight through Saturday. A few strong storms will be possible, with the greatest chance over SE GA on Friday.

PRELIMINARY POINT TEMPS/POPS

AMG 74 59 72 53 / 20 60 90 60 SSI 70 58 70 56 / 0 40 80 80 JAX 77 58 79 56 / 0 20 80 80 SGJ 75 59 79 57 / 0 10 60 70 GNV 76 57 80 57 / 0 10 60 70 OCF 77 56 81 58 / 0 0 40 60

JAX WATCHES/WARNINGS/ADVISORIES

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