Marine Weather and Tide Forecast for St. Marys, GA

UPDATE
Minor changes to the forecast to reflect ongoing conditions impacting several active wildfires across northeast Florida. Gusty winds will shift more northeasterly tonight as the front moves through, with a few showers popping up near the front over north central Florida. Smoke will be present south of ongoing wildfires, surface observations showing impacts near Gainesville, Green Cove Springs, and Lake City at this time. Winds remain breezy through the day Monday as drier air is in place behind the front, continuing fire weather concerns. The Fire Weather Watch currently in place for Monday will likely be upgraded with the forecast tonight, for at least part of the watch area.

SHORT TERM /THROUGH TUESDAY NIGHT/
Main Highlights This Period:

- Fire Weather Watch Monday - Critically low minimum humidity values inland each day - A period of elevated onshore flow Monday

On Monday, the broad base of a mid-upper level trough will exit the area with rising heights as ridging builds in through early Tuesday.
In it's wake and behind the cold front from today, strong high pressure builds in from the northwest and north keeping the pressure gradient tight against the departing front. This will produce breezy northeast flow for much of the area but especially near the coastal areas from Fernandina Beach southward.

Dry air from the sfc to aloft will help lower dewpoints for Monday into the 20s and 30s where we have a fire weather concerns. This combined with the gusty winds will create dangerous fire weather conditions, mainly for inland southeast GA and northeast FL.

The temperatures on Monday will be near to slightly below normal in the mid 70s coast to about 80 degrees inland. Monday night sees mostly clear skies. This will help lead to decent radiation cooling given that winds should quickly drop off as a piece of the high pressure system gets centered over portions of the area. Lows are forecast all the way down to 45-50 degrees inland and mid 50s at the coast.

On Tuesday, increased ridging aloft will help rebuild high pressure to the north of the area. Onshore flow and stable conditions will lead to a pleasant day with highs a bit closer to normal. Still, given the severe drought and some occasional breezy winds, fire weather concerns remain high. Tuesday night, not as cool with lows in the 50-60 deg range with some airmass moderation from the onshore flow and perhaps a few more high clouds moving in ahead of a mid level trough over the central Gulf coast.

LONG TERM /WEDNESDAY THROUGH SUNDAY/
Main Highlights This Period:

-Dry conditions persist into next week into Friday -Isolated T'storms possible Saturday and Sunday -Warming Trend this Period

Shortwave trough will bring a period of some high clouds over the region Wednesday through Thursday morning while surface high pressure ridge will settle into the area with fairly weak sfc flow except for a breezy afternoon sea breeze at the coast. Some increase in low level moisture expected due to the east-southeast low level flow.
Thursday onward, the ridge of high pressure at the sfc and aloft looses some of its strength with the sfc high pushing further offshore to the east and southeast. This will result in further warm up but still largely dry conditions. PWATs do rise a bit from 0.70 inches on Wednesday to about 1.2 inches by Saturday and Sunday, which is at or slightly above the norm for this time of year.
By Saturday into Sunday, a weak cool front will move into the eastern U.S., but remains to the north and northwest of our area. There may be enough moisture to kick off a few showers or thunderstorms on Saturday (forecast POPs of 20-30 percent), mainly forced from the west and east coast sea breezes.
Dewpoints at least rise to upper 50s and lower 60s bringing in some better sfc moisture. However, confidence in this latter POP forecast is a bit uncertain given the relatively dry conditions persisting.

Temperatures will begin with highs near normal Wednesday and above normal Thursday into Sunday. Low temperatures will be near normal through Friday and slightly above normal on Saturday and Sunday.

AVIATION /00Z MONDAY THROUGH 00Z TUESDAY/
VFR conditions will persist through TAF period, with the exception of nearby wildfires causing deteriorating conditions at GNV this evening. Winds shift to north-northeasterly after 00Z, with gusty winds continuing along the coastal sites overnight as a front moves through.

MARINE

A cold front will bring a surge of northeast winds following the frontal passage through Monday night. Small Craft Advisories are in place from tonight and into Monday Night. Winds and waves subside Monday night as high pressure builds into the area for mid-week.

Rip Currents and Surf:

A low to moderate risk of rip currents Today due to offshore west to northwest flow ahead of a cold front. High/moderate risk of rips expected early this week as a strong NE wind surge develops behind the cold frontal passage.

FIRE WEATHER

On Monday, strong high pressure will build in from the northwest with breezy northeast winds near 15 mph gusting to 25 mph and critical MinRH values 15-20 percent will create dangerous wildfire conditions and a Fire Weather Watch is in effect for all of inland Southeast GA in addition to Northeast FL locations along and just south of the Interstate 10 corridor. The breezy surface and transport winds will create high dispersions Monday.

High pressure will be over the area Tuesday and Wednesday before gradually moving east of the area Thursday into Friday, with dry conditions persisting and critical MinRH values over inland Southeast GA and portions of northeast FL each day this week. Breezy east to northeast winds Tuesday will diminish Wednesday with daily Atlantic seabreeze moving well inland into Friday. Areas to widespread high daytime dispersions are expected daily into at least Thursday due to high mixing heights and moderate transport wind speeds.

FOG POTENTIAL AND OTHER REMARKS: There will be potential for Localized "superfog" near the vicinity of any smoke from ongoing wildfires

PRELIMINARY POINT TEMPS/POPS
AMG 47 80 48 82 / 0 0 0 0 SSI 60 73 57 74 / 0 0 0 0 JAX 55 77 50 80 / 10 0 0 0 SGJ 63 75 57 77 / 10 0 0 0 GNV 55 81 48 84 / 20 0 0 0 OCF 59 81 50 84 / 20 0 0 0

JAX WATCHES/WARNINGS/ADVISORIES
FL...Fire Weather Watch from Monday morning through Monday evening for FLZ021-023-024-030-031-035-120-136-220-232-236-322- 422-425-522.
High Risk for Rip Currents from Monday morning through late Monday night for FLZ124-125-138-233-333.
Fire Weather Watch from Monday morning through Monday evening for FLZ225.
GA...Fire Weather Watch from Monday morning through Monday evening for GAZ132>136-149-151>153-162-163-165-250-264-350-364.
Red Flag Warning until 8 PM EDT this evening for GAZ132-133- 149.
MARINE...Small Craft Advisory until 11 AM EDT Monday for AMZ450.
Small Craft Advisory until 8 PM EDT Monday for AMZ452-470-472.
Small Craft Advisory from 11 PM this evening to 8 PM EDT Monday for AMZ454.
Small Craft Advisory from 11 PM this evening to 2 AM EDT Tuesday for AMZ474.