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

- Patchy Dense Fog Possible North-Central FL Early Monday and Tuesday Mornings.

- Moderate risk of rip currents for area beaches Today and Monday.

NEAR TERM /THROUGH TONIGHT/

Rest of this afternoon: Weak high pressure ridge building just north of the local area under Mostly Sunny skies will still lead to nice bounce back of temps into the 60s over inland areas, while a surge of NE winds around 15 mph down the Atlantic Coast will hold Max Temps only in the 50s from JAX northward along the SE GA coastal areas.

Tonight: Weak high pressure ridge will in place across the region at the surface while increasing moisture aloft will build mid and high clouds from the west through the overnight hours. Near calm winds and mostly clear skies to start the night will allow for temps to crash after sunset, with likely Min Temps occurring around midnight tonight, then steady or even some slight rise in temps towards sunrise Monday morning. Overall expect another chilly night inland with overnight lows in the mid/upper 30s, but expect temps to remain above freezing and increasing cloud cover should limit frost formation, so have left out of the forecast grids for now. Min Temps in the lower/middle 40s closer to the Atlantic Coast. The weak onshore flow will lead to some increase in low level moisture levels, which will contribute to some patchy/areas of fog formation along the St. Johns River Basin to the south of JAX, mainly between the I-95 and US 301 corridors. Not expecting significant dense fog formation, but super fog formation is possible if this develops near any lingering wildfire smoke in areas across NE FL.

SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/

A northwest flow aloft starts the short term period with a shortwave trough moving through the forecast area, and moving into central FL by Monday evening. The mid level flow turns more northerly into early Tuesday as a shortwave ridge moves over the area then quickly more zonal by Tuesday afternoon/evening as another broad trough and shortwave troughs move into the eastern CONUS. At the surface, a 1032 mb high pressure system over VA/NC will move southeast with a weak, dry frontal boundary shifting southward over the area waters, possibly near the southeast GA coast, but there's little sensible weather associated with it. This boundary moves back north Monday night as weak high pressure builds in over central and north central FL area Tue into Tue night.

Should see partly to mostly cloudy skies early Monday then clearing as the shortwave trough moves out of the area. Another batch of some partly cloudy skies at times on Tuesday as the second area of shortwaves moves into the eastern U.S., with more mostly cloudy skies Tuesday night with a few sprinkles possible late. Temperatures near seasonable values Monday-Monday night and then above seasonal values Tuesday. Patchy fog possible early Tuesday and Wednesday mornings, but no widespread fog expected at this time.

LONG TERM /WEDNESDAY THROUGH SUNDAY/

Shortwave energy trough passes over the region on Wednesday bringing low chances for showers to SE GA through Wednesday night and anticipate mostly cloudy skies for most area. An associated cold front sinks southward into the SE US Wednesday, moving into our area Wednesday night per consensus of GFS and ECMWF. This boundary looks to move through our area Thursday and tending to wash out, loosing some definition. Does not look like much chance of rain Thursday with POPs generally less than 15 percent per model blend. The front will move back north as a warm front over the area Thursday night into Friday morning as a frontal wave develops over the Gulf coast states. Could be some patches of dense fog around Thursday night due to the warm front and light sfc winds. Models continue to differ on how the upper pattern evolves and the strength and placement of the frontal wave. For now, have low chances for showers on Thursday night and then increasing chances area-wide for Friday into the weekend. Best chances for beneficial rain will be this weekend with the frontal passage. No thunderstorm potential is noted in the forecast at this time, but a thunderstorm mention could be needed in subsequent forecasts if instability develops more than the current forecast of around 300 J/kg or less. Above seasonable temperatures continue through Friday as continued southwesterly flow ushers in Gulf air/moisture to the area. Temp forecast over the weekend is uncertain given the differing model solutions, but currently we show slightly above normal temps.

AVIATION /18Z SUNDAY THROUGH 18Z MONDAY/

Prevailing VFR through 18z Monday with increasing mid and high clouds this evening and through the overnight hours. Some onshore winds in the 6-10 knot range to start the afternoon, then winds becoming 4 knots or less after sunset. Slightly better chances for some low level fog at GNV/VQQ/SGJ tonight in the 15-25% range, but despite the slight increase in low level moisture, the increase in clouds overnight and lack of any recent rainfall, will continue to downplay fog potential at local terminals with this forecast package.

MARINE

High pressure will build northeast of the local waters tonight into Monday. A long period easterly swell will maintain elevated combined seas through Tuesday as the surface high builds east of the Florida peninsula. The high will shift southeast of the region Wednesday as a weakening front approaches with increasing westerly winds and a low chance of showers. The front is expected to stall and linger over the Florida peninsula Thursday, then morph into a lifting warm front late Thursday into Friday.

Rip Currents: Solid Moderate rip current risk today and Monday with Northeast winds and elevated combined seas with building easterly swells with periods of 10-12 seconds. This will result in surf/breakers of 3-4 ft, occasionally up to 5 feet at times.

FIRE WEATHER

- Areas Of Low Daytime Dispersions Today And Monday - Low Min Rh Values Inland Today

Dry weather conditions will prevail through early this coming week. Rest of today, light and variable winds inland will lead to poor to low dispersions with low min RH values inland in the mid to upper 20s.

On Monday, surface and transport winds again remain weak as high pressure builds into the region leading to low daytime dispersions across the area, especially near the coast. Easterly flow will increase moisture to coastal areas today but critically low humidities in the upper 20s to around 30 percent expected inland, generally near and west of U.S. Highway 301. Moisture gradually increases by Wednesday when mid RH values are in the 40 to 50 percent range. No significant precipitation chances expected until mid-late week when a cold front moves into the area.

FOG POTENTIAL AND OTHER REMARKS: Patchy to areas of fog will be possible across north-central FL early Monday and Tuesday mornings, especially if it mixes with nearby wildfire smoke.

PRELIMINARY POINT TEMPS/POPS

AMG 36 68 41 74 / 10 10 0 0 SSI 42 61 45 69 / 10 10 0 0 JAX 40 68 41 78 / 10 10 0 0 SGJ 43 67 44 73 / 10 10 0 0 GNV 39 73 39 78 / 10 10 0 0 OCF 38 73 39 78 / 10 10 0 0

JAX WATCHES/WARNINGS/ADVISORIES

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