Marine Weather and Tide Forecast for Jacksonville Beach, FL

UPDATE
Forecast remains on track for today with mostly clear skies, outside of scattered to broken high clouds and some occasional cumulus clouds. Main changes were to adjust the temps and dewpoints for latest trends.

NEAR TERM /THROUGH TONIGHT/
- Dry & warm weather persist with near record high temperatures over inland locations

- Critically low minimum humidity values inland SE GA Saturday

- Elevated Fire Concerns

High pressure will steadily clear the area as a cold front shifts towards the area from the west, with the front pushing into the area on Sunday. Warm and dry conditions will once again be present.
Temperatures are expected to range in the lower to mid 90s across inland locations, with daytime highs flirting once again with record highs, while the southeast onshore breeze will keep coastal locations in the mid to upper 80s. Southerly-southwesterly flow, with winds of 8-12 mph, will allow for the Gulf breeze to push well inland, keeping the Atlantic breeze mostly confined along locations east of the St. Johns River. Dry conditions across the inland locations will once again be of concern for any ongoing fire or new fires that may develop as gusts along the sea breezes range from 15- 20 mph.

By the evening hours, lows will be in the lower 60s along inland locations, while coastal locations will mainly be in the mid to upper 60s. Could see some patchy fog develop Saturday Night along interior locations as low level moisture remain with the southwesterly flow from the Gulf.

SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/
Main Highlights This Period:

- Patchy fog potential Sunday morning inland - Critically low minimum humidity values inland each day - Fire Weather Watch along and south of I-10 over inland NE FL - A period of elevated onshore flow behind the front Monday.

Sunday, a mid to upper level trough will move across the SE states, pushing a cold front into SE GA by midday and into NE FL during the afternoon with limited moisture and only a widely isolated shower over land, but isolated coastal showers Sunday afternoon into early evening may shift onto the Flagler county coast, but otherwise not expecting measurable rainfall for a majority of the area. The winds just ahead of the front will become westerly by late morning, increasing to 15-20 mph and gusting to 25-30 mph, then turning NW as the front moves through during the day. The driest air will arrive in the mid to late afternoon hours over inland SE GA, but still very questionable as to whether humidity levels will be low enough to support a need for a Fire Weather Watch on Sunday as winds will be conducive around 15 mph gusting to 25 mph, but the duration for much drier humidity levels under mostly cloudy skies will be very short, if at all, before sunset as winds will begin to subside to well under Red Flag criteria.

Highs Sunday will be above normal, but less so with low to mid 80s over SE GA and the upper 80s to near 90 degrees for most of NE FL with low 90s along the southern St Johns river basin westward into north central FL.

Sunday night into Monday, winds along the coast will remain breezy from the north overnight turning NE into Monday morning as the front exits south of the area. Ridging aloft will move eastward in the wake of the trough axis extending into northern FL that will move offshore by afternoon, allowing strong surface high pressure to build in from the NW with NE winds 15-20 mph over much of NE FL gusting to 30 mph along the coast and 25 mph inland. A very dry airmass will be filtering into the area with very low dewpoints into the mid 20s across interior SE GA west of highway 301 Monday midday to afternoon and into the 30s away from the coast, yielding minimum relative humidity values to 15-20 percent over inland SE GA and 20-25 percent along and west of highway 301 over NE FL.

The combination of breezy NE winds and very low humidity will lead to increasing potential for dangerous wildfire conditions and a Fire Weather Watch has been expanded to include western Duval, western Nassau, and Clay counties westward into the Suwannee Valley and Echols county in SE GA.

Highs on Monday will be below normal along the coast and I-95 with mid to upper 70s, warming to near normal values inland near I-75 into the upper 70s to low 80s. Lows Monday morning will be below normal across inland SE GA with upper 40s to around 50, above normal along the coast into the low 60s, and near normal over NE FL with mid to upper 50s.

LONG TERM /TUESDAY THROUGH FRIDAY/
Main Highlights This Period:

-Dry conditions persist into next week -Critically low Relative Humidity Values Inland each day

High pressure will build to the north Tuesday and then gradually shift east of the area Wednesday into Friday. Winds from the ENE Tuesday will diminish across SE GA, but remain breezy along the coast and NE FL areas. Winds will decrease with east to SE flow prevailing Wednesday through Friday with daily Atlantic seabreeze pushing well inland each day. Dry and mostly sunny conditions will continue with low humidity values over inland NE FL while inland SE GA will have critically low humidity values each afternoon.

Temperatures will begin with highs near normal Tuesday into Wednesday becoming above normal Thursday and Friday. Below normal low temperatures Tuesday morning will rise to near normal values Wednesday through Friday.

AVIATION /12Z SATURDAY THROUGH 12Z SUNDAY/
VFR. Light southwest to west winds return around 14Z. Inland movement of sea breezes will bring an uptick in winds for the TAF sites around 17Z-20Z for coastal sites, a bit past 20Z/21Z for inland locations.

MARINE

Surface high pressure ridging will push south of the area by Saturday night. Atlantic sea breeze expected to push inland during the afternoon, bringing a wind shift to the southeast with winds up to 15 knots. A dry cold frontal passage is expected late Sunday afternoon into Sunday Night, then a surge of northeast winds follows the frontal passage through Monday night and Small Craft Advisory with the potential for Gale force gusts are expected. High pressure will develop over the area Tuesday, moving east of the area by Wednesday.

Rip Currents and Surf:

Moderate Risk of Rips will continue for area beaches primarily due to the easterly swells of about 2 to 2.5 ft with periods of 8 seconds. A small window of wind wave action today as the Atlantic sea breeze develops during the afternoon. A low risk of rip currents Sunday due to offshore west to northwest flow ahead of a cold front.
High risk of rips and potential high surf advisory conditions expected early next week in strong NE wind surge behind cold frontal passage.

FIRE WEATHER
-Critically low MinRH values Today over inland Southeast Georgia and much of inland Northeast Florida

-Areas of high daytime inland dispersions Today

-Near Critical MinRH values Sunday afternoon over inland Southeast Georgia

-Widespread high daytime dispersions Sunday through Friday

High pressure will be over the area today with dry mostly sunny, and very warm conditions and combined with the exceptional/extreme drought, will continue the elevated fire risk across the area.
Critically low Min RH values expected today over inland Southeast Georgia 23-28 percent and 25-30 percent over inland Northeast Florida. The East and Gulf seabreeze will meet near highway US-17 by late this afternoon. Increasing transport winds will create high dispersions across inland Southeast GA and the Suwannee Valley.

Dry conditions will persist into the next week as a cool front moves through Sunday. A cold front arriving late Sunday will bring about a wind direction change to west and northwest Sunday afternoon to the north and northeast Sunday night becoming very breezy, but clouds and moisture ahead of the front appear to prevent MinRH values from falling below critical levels until near sunset, limiting potential for Red Flag conditions. Monday, very breezy northeast winds and well below critical MinRH values 15-20 percent will create dangerous wildfire conditions with a Fire Weather Watch in place along and just south of Interstate 10 west of Jacksonville and including Clay, western Duval, western Nassau, and Echols county.

FOG POTENTIAL AND OTHER REMARKS: Patchy inland fog will develop each morning into this weekend. There will be potential for Localized "superfog" near the vicinity of any smoke from ongoing wildfires.

CLIMATE
Record High Temperatures at NE FL/SE GA climate sites:

April 18: JAX 94/1967, CRG 89/2018, GNV 91/1967, AMG 92/1967

April 19: JAX 92/1995, CRG 91/2013, GNV 94/2011, AMG 91/1968

PRELIMINARY POINT TEMPS/POPS
AMG 92 63 82 48 / 0 0 10 0 SSI 85 68 85 58 / 0 0 10 10 JAX 93 65 90 56 / 0 0 10 10 SGJ 88 66 89 63 / 0 0 0 10 GNV 93 62 91 57 / 0 0 0 0 OCF 92 63 90 60 / 0 0 0 0

JAX WATCHES/WARNINGS/ADVISORIES
FL...Fire Weather Watch from Monday afternoon through Monday evening for FLZ021-023-024-030-031-035-120-136-220-232- 236-322-422-425-522.
GA...Fire Weather Watch from Monday afternoon through Monday evening for GAZ162.
MARINE...None.