Marine Weather and Tide Forecast for Jacksonville, FL

UPDATE
Temperatures have warmed above freezing, so allowed the Freeze warning and the frost advisory to expire at 9AM.

Surface high pressure is centered over MD/VA/NC while extending a surface ridge axis southwestward into GA. The ridge axis will sink southward today as the center of the high shifts away to the northeast. A weak coastal trough will form late today with northerly winds becoming northeasterly this afternoon and breezy at the immediate NE FL coast 15-20 mph gusting to 25 mph, 5-10 mph with occasional gust to 15 mph over SE GA and 10-15 mph gusting to 20 mph over inland NE FL.

Sunny skies will become mostly sunny to partly cloudy after lunch as mid and high level clouds shift into the area this afternoon as a shortwave aloft arrives from the northwest. The sunshine and and slowly rising heights will allow highs to warm up about 4-8 degrees compared to yesterday into the low 60s over SE GA and the mid 60s over NE FL with a few isolated upper 60s over north central FL.

NEAR TERM /THROUGH TONIGHT/
Main Highlights through Tonight:

- Light Freeze/Widespread Frost expected this morning inland SE GA and along the I-75/I-10 corridor of inland North FL.

Early this morning: Light Freeze/Widespread frost still on track over inland areas this morning with lows around 30F, despite some high clouds aloft. Lows generally closer to 40F along the Atlantic Coast as N-NE flow remains around 10 mph there.

Record Low Minimum temps for March 18 are listed here...

JAX 32/1971
CRG 37/1978
GNV 29/1962...AMG 30/1971

Rest of Today: High pressure ridge axis over GA/Carolinas sinks slowly southward with dry air mass still in place aloft, and just expect periods of high clouds from time to time. Surface winds shift slightly to the N-NE and increase to breezy levels along the Atlantic Coast/I-95 corridor around 15G25 mph, with lesser winds around 10G15 mph over inland areas. Temps still below normal today, but slightly warmer than Tuesday with lower 60s across SE GA and middle 60s across NE FL.

Tonight...Skies become mostly clear by the overnight hours as high pressure ridge sinks southward across south GA, which leads to another chilly night with below normal temps and lower in the middle 30s across inland SE GA and upper 30s/lower 40s across inland NE FL, which could support another round of patchy/areas of Frost, but coverage would likely not be enough to warrant Frost Advisories.
Closer to the Atlantic Coast, N-NE surface flow will remain elevated at 10-15G20 mph and low temps will only fall into the 40s.

SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/
Main Highlights This Period Wed-Thu:

-Areas of frost over inland Southeast Georgia Thursday morning -Moderating temps daily through the end of the week

Elongated surface high pressure will remain the dominant feature through the end of the week, slowly repositioning towards directly over or west of the region through the same time frame. An isolated shower cannot be ruled out near the immediate coastline of St. Johns and Flagler Counties on Thursday and Thursday Night with modest onshore flow continuing, but otherwise generally benign weather is expected for the short term with dry and cooler than normal temps moderating each day. Temps Thursday will range from the mid to upper 60s for the coast and portions of interior southeast GA to the low to mid 70s inland. Lighter onshore flow Friday will allow 70s for almost everybody. Low temps will range from the 40s to near 50 Thursday Night to the mid 40s to low 50s Friday Night.

LONG TERM /SATURDAY THROUGH TUESDAY/
Main Highlights This Period: Friday to Monday.

- Warming trend late in the period and dry through next Monday - Next chances for rain with a frontal boundary Monday Night & Tuesday

Mid to upper level troughing will exit off the eastern seaboard this upcoming weekend with this flow becoming more zonal. This will allow surface high pressure to move over/just south of the region this weekend before shifting offshore into the Atlantic early next week.
This also results in temperatures continuing to moderate throughout the long term period as dry weather persists and flow becoming more south to southwesterly. The next frontal boundary looks to drop southward towards the region around Monday Night into Tuesday, likely stalling nearby heading into mid next week.

AVIATION /12Z WEDNESDAY THROUGH 12Z THURSDAY/
The 12Z TAF period will feature VFR conditions through the entire TAF period. High pressure to the north will sink south towards the area with high clouds later today. Northerly winds will increase after 15Z to around 10 knots inland with gusts to around 15 knots and a little higher along the coast 12-15 knots gusting to around 20 knots. High clouds continue tonight into early Thursday morning with winds backing north and lightening to under 10 knots inland to near 10 knots gusting to 15 knots at the coast.

MARINE

Winds become north-northeast this morning as high pressure shifts northeastward towards the Mid-Atlantic coast. This strengthening high pressure center will wedge down the southeastern seaboard, creating another round of Small Craft Advisory conditions over the Northeast Florida waters later tonight and Thursday. Winds and seas are expected to diminish by Friday as high pressure center builds into the region and settles over the local waters this weekend.

Rip Currents: A moderate risk of rips is expected Today as flow becomes N-NE and increases this afternoon with surf/breakers in the 2-4 ft range. Further increase in N-NE flow tonight into Thursday will lead to a potential high risk of rips for NE FL beaches with surf/breakers into the 3-5 ft range, with a Moderate risk continuing for the SE GA beaches.

FIRE WEATHER
- Areas Of Critically Low Min Rh Inland Through Thursday

Cool and dry high pressure will remain in place through at least the end of the week, which will persist low to critically low daytime RH values through Thursday. Dispersions will also be fair to good area wide through the next several days, with primarily northeasterly low level flow trending slightly downward each day. This flow will be strongest further south and east closer to a maritime influence.
Conditions look to remain dry with benign weather throughout the weekend as well, with the next frontal boundary approaching sometime Monday Night/Tuesday.

FOG POTENTIAL AND OTHER REMARKS: Significant fog potential is not expected the next couple of days. A light freeze expected for Southeast Georgia and inland Northeast FL this morning, with areas of frost between about Trail Ridge and the St. Johns River as well as more coastal GA.

PRELIMINARY POINT TEMPS/POPS
AMG 61 34 69 43 / 10 10 0 0 SSI 59 43 64 48 / 10 10 0 0 JAX 63 41 69 45 / 10 10 0 0 SGJ 62 46 66 50 / 10 10 0 0 GNV 66 40 72 43 / 10 10 0 0 OCF 68 40 73 44 / 10 10 0 0

JAX WATCHES/WARNINGS/ADVISORIES
FL...None.
GA...None.
MARINE...Small Craft Advisory from 4 AM to 4 PM EDT Thursday for AMZ452- 454-472-474.