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

- Periods of Beneficial Rainfall through Today & Tonight. Isolated TStorms Possible South of I-10 Today. A Strong Storm is Possible over Marion, Putnam, and Flagler. Locally Heavy Rain at times

- Patchy to Areas of Fog this morning and late Tonight

- Light Freezes & Frost Possible Inland on Mon & Tues Nights

- Small Craft Advisory possible Monday Afternoon into Tuesday

UPDATE

A messy, dreary day across northeast FL and southeast GA today as rounds of stratiform rain and drizzle push across the area. There weren't any significant adjustments to the forecast with the update.

Latest mesoscale analysis, does indicate continued orginization of surface trough beneath an upper impulse traveling across the northern Gulf coast. As the weak low spins up, it should result in a southerly wind response and lead to weak instability across central FL this afternoon. The main question will be how far north will the front lift... At this time, it appears that the stalled boundary will lift northward toward Marion, Putnam, and Flagler counties this afternoon. Though confidence is low in terms of thermo instability, a favorable shear profiles (low- level and deep layer) are at play but if instability is nulled this effectively will negate the impacts of available shear. Still it is possible to that an isolated thunderstorm or two develop that could develop and tap into the dynamic shear profile.

Otherwise, areas to the north will be wet, drizzle, overcast and cool through the rest of the day.

NEAR TERM /THROUGH TONIGHT/

A rainy and cool day today as upglide/isentropic lift occurs north of a stalled front across north central FL. The frontal boundary is forecast to lift north as a warm front into northeast FL to near a Gainesville to St Augustine line by around 18z, with the GFS slower and weaker with the front moving northward. This occurs as a couple of waves of low pressure form along the front over the northern Gulf and off the northeast FL coast. A strong shortwave trough will move into the lower and mid MS valley by this evening which will help translate the waves of low of pressure east and southeast and thereby the front back southward. A weak trough may form north of the front this evening due to the strong shortwave moving into the southeast, with this trough moving offshore to the east late tonight

High POPs are in store with rich deep layer moisture in place with deep layer RH at 90+ percent, upper level divergence south of an upper level jet, and moderately strong upglide. Isolated thunderstorms are forecast over portions of northeast FL where MUCAPE may reach 400-700 J/kg. An isolated strong to severe storm is possible given the instability and 0-6km bulk shear of 40-50 kt, based off the most recent HRRR, across Marion county, possibly far south Putnam and Flagler county, and also noted in the latest SPC outlook. Periods of moderate to locally heavy rainfall are anticipated over far southeast GA and all of northeast FL. The main band will set up near the I-10 corridor, expand in coverage, and then shift southeastward into the evening. The rainfall intensity should break up by the mid to late evening hours.

Highest rainfall accumulations today are expected across NE FL where 1-3" of beneficial rainfall will be possible. Not expecting this to bust the drought given the deficit but it's a trend in the right direction.

With the wet weather, gloomy overcast skies continue to keep high temps below normal with temps ranging from mid 50s over southeast GA, around 60 for the I-10 corridor, and around 70-75 deg for the far southeast portions. Lows tonight drop to the upper 40s for southeast GA and the 50s for northeast FL. Patchy to areas of fog will also affect the region both this morning and again late tonight, primary due to the low clouds.

AVIATION /12Z SUNDAY THROUGH 12Z MONDAY/

Widespread stratiform rains, with embedded heavier showers are expected over the forecast area today. We expect widespread IFR with occasions of LIFR. There may some occasional improvement in cigs for brief periods in rain/showers due to low level mixing by mid to late today. The rain and shower intensity does increase starting at about 15z and continues until about 23z/00z. The persistent rains end at SSI about 04z Monday, and for northeast FL TAFs around 05z-07z Monday. There is a small window for brief thunder at GNV from about 18z - 22z, and due to the low chance will leave out at this time. Sfc winds will trend to the north to northeast at or below 10 knots through tonight. There may some briefly gusty winds as showers translate east-southeast across the GNV and SGJ terminals this afternoon.

MARINE

A frontal boundary will remain stalled south of the coastal waters early today. A wave of low pressure will then develop along this front and move south of the northeast Florida waters late today bringing widespread rainfall and an isolated embedded thunderstorm this afternoon through tonight. Low pressure will move offshore Monday morning, resulting in breezy northwest winds. Northerly winds then strengthen with building seas to Small Craft Advisory levels early next week. Weak high pressure will build over the area by Wednesday and then shift southeast of the forecast area on Thursday as another cold front approaches from the northwest.

Rip Currents: SE GA Low Monday NE FL Moderate Monday

FIRE WEATHER

LOW DAYTIME DISPERSIONS TODAY...

A frontal zone will provide wet weather over the region through Monday morning. High pressure will build to the northwest Monday night, then build overhead Tuesday. The high will sink to the southeast Wednesday through Thursday. The cold front will move southeast across the region Friday into Friday night. Strong high pressure will build to the northwest Saturday.

FOG POTENTIAL AND OTHER REMARKS: Reduced visibilities in the early morning hours and associated with heavy rainfall. Thunderstorm potential over NE FL through tonight. Light Freeze with frost likely over SE GA Tuesday night.

PRELIMINARY POINT TEMPS/POPS

AMG 46 57 34 53 / 40 30 0 0 SSI 51 60 42 54 / 50 20 0 0 JAX 52 64 41 60 / 60 10 0 0 SGJ 57 67 49 63 / 80 20 0 0 GNV 55 68 42 64 / 80 20 0 0 OCF 58 70 45 66 / 90 20 0 0

JAX WATCHES/WARNINGS/ADVISORIES

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