Marine Weather Net

Altamaha Sound to Fernandina Beach FL Marine Forecast


TONIGHT

S
WINDS
10 - 15
KNOTS

THURSDAY

S
WINDS
5 - 10
KNOTS

THURSDAY NIGHT

S
WINDS
10 - 15
KNOTS

FRIDAY

S
WINDS
10 - 15
KNOTS

The Marine Weather Forecast In Detail:
AMZ450 Forecast Issued: 255 PM EDT Wed Jul 06 2022

Tonight...South Winds 10 To 15 Knots Becoming Southwest 5 To 10 Knots Towards Daybreak. Seas 3 To 4 Feet With A Dominant Period 8 Seconds. A Light Chop On The Intracoastal Waters.
Thursday...South Winds 5 To 10 Knots Becoming Southeast 10 To 15 Knots In The Afternoon. Seas 3 To 4 Feet With A Dominant Period 8 Seconds. A Moderate Chop On The Intracoastal Waters. Slight Chance Of Showers And Thunderstorms In The Afternoon.
Thursday Night...South Winds 10 To 15 Knots. Seas 3 To 4 Feet With A Dominant Period 5 Seconds. A Light Chop On The Intracoastal Waters. Slight Chance Of Showers And Thunderstorms In The Evening.
Friday...South Winds 10 To 15 Knots. Seas 3 To 4 Feet. A Moderate Chop On The Intracoastal Waters. Chance Of Showers And Thunderstorms In The Afternoon.
Friday Night...Southwest Winds 10 To 15 Knots. Seas 3 To 4 Feet. A Light Chop On The Intracoastal Waters. Slight Chance Of Showers And Thunderstorms.
Saturday...Southwest Winds 10 To 15 Knots. Seas 2 To 3 Feet. A Moderate Chop On The Intracoastal Waters. Chance Of Showers And Thunderstorms.
Saturday Night...Southwest Winds 10 To 15 Knots. Seas 2 To 3 Feet. Chance Of Showers And Thunderstorms.
Sunday...Southwest Winds 10 To 15 Knots Diminishing To 5 To 10 Knots In The Afternoon. Seas 2 To 3 Feet. Showers And Thunderstorms Likely.
Sunday Night...Southwest Winds 5 To 10 Knots Becoming West After Midnight. Seas 2 Feet. Showers And Thunderstorms Likely.
Monday...Northwest Winds 5 To 10 Knots Becoming Northeast In The Afternoon. Seas 2 To 3 Feet. Showers And Thunderstorms Likely.
SHARE THIS PAGE:           
Area Forecast Discussion
National Weather Service Jacksonville FL
358pm EDT Wednesday July 6 2022

...ABOVE NORMAL WARMTH THROUGH SATURDAY WITH HEAT INDICES 105-110... ...STORMY WEATHER SUNDAY AND MONDAY... Near Term - Through Tonight
Weak easterly 1000-500 mb steering flow was across NE FL with the ridge axis extending across south GA. The presence of the ridge was keeping convection very shallow in nature across SE GA despite PWAT (Precipitable Water) content above normal. Deeper convection was across NE FL. forming near and inland of the inland progressing east coast sea breeze and St. Johns River breezes. Another batch of deeper convection was firing along the slowly inland progressing west coast sea breeze, just now over Gilchrist, SW Alachua and western Marion counties. Through this evening, convection will continue to migrate inland with a sea breeze and boundary collision near the I-75 corridor across NE FL. Another areas of isolated storms will be near the western Altamaha and Ocmulgee River basins where storm outflows from the north could approach through sunset. The main weather hazard with storms today will be locally heavy rainfall given slow storm motion and high PWAT (Precipitable Water) content. There could be some gusty downdraft winds in stronger cells, but, at this time severe weather is not likely. After sunset, precipitation will quickly fade with loss of instability and forcing with mostly clear skies after midnight and possibly some inland patchy fog especially where recent rainfall occurred. Muggy low temps will range in the mid/upper 70s to near 80 along the St. Johns River basin & Atlantic coast.

Short Term - Thursday Through Friday Night
The mean layer ridge axis will shift southward from across south GA today to across NE FL into Friday with a continuation of above normal PWAT (Precipitable Water) > 2 inches. Weak steering flow Thursday will enable both west and east coast sea breezes to drift inland with convergence of boundaries and thus the highest rain chances across the interior late Thu afternoon/evening where scattered showers and isolated t'storms are expected between Trail Ridge and I-75. The main difference Thursday compared to today will be more coverage of storms across SE GA especially near the Altamaha River basin as upstream convection near the frontal zone edges farther south, with a little less coverage of storms across the central part of the forecast area under the ridge axis. By Friday, the focus for storms will increase across SE GA as PWAT (Precipitable Water) increases to near 2.5 inches with more scattered convection across NE FL under stronger westerly steering flow and a pinned east coast sea breeze at the coast. Severe storm potential still looks low both days given lack of upper level forcing or significant mid level instability given 500 mb temps above climo around -5 degC. The threat for locally heavy rainfall increases Friday as slow moving frontal outflows drift southward into the SE GA over a moisture laden airmass. Above normal temperatures with heat index values 105-110F, which will hover near local Heat Advisory criteria each day. High temperatures will range in the mid/upper 90s with lows in the mid/upper 70s.

Long Term - Saturday Through Wednesday

A stormy pattern sets up into early next week. Westerly steering flow increases Saturday as the mean layer ridge shifts farther south across the FL peninsula and the upper level ridge centered over the deep south begins to break down, enabling a mean layer trough to deepen down the eastern seaboard into early next week. Scattered to numerous diurnally enhanced showers and storms are expected to increase progressively southward each day, with stormy days for much of the area Sunday into Monday as the surface front edges southward and lingers across the local forecast area. By mid-week, the upper level ridge begins to rebuild northward from south FL, shifting the deeper moisture plume north of the area and a gradual lowering of rain chances. Temperatures will begin to trend near normal to possibly below normal with highs in the upper 80s to low 90s and lows in the low/mid 70s under partly to mostly cloudy skies.

Marine
Surface high pressure will extend across south Florida through the weekend as a surface front edges southward across Georgia. Prevailing south to southwesterly winds will increase to near Small Craft Exercise Caution levels over the outer waters Thursday and Friday night as the front approaches. Winds will become onshore near the coast with the east coast sea breeze Thursday. The front is expected to shift south and linger across the local waters early next week.

Rip Currents
A moderate rip current risk is expected through Thursday.

Fire Weather
Warm and unstable with numerous to scattered mainly inland afternoon and early evening showers and thunderstorms. Southwest to south winds will develop each night and during the early morning, then sea, river and lake breezes will develop into the afternoon. The east coast sea breeze will move inland Thursday afternoon toward the Highway 301 corridor. Friday the east coast sea breeze will make less progress inland and likely be pinned near the Atlantic coast in the late afternoon. Winds gusts near 25 mph will be possible trailing the east coast sea breeze Thursday. A front will approach south Georgia from the north Friday, with elevated dispersion possible near the Altamaha River basin.

NOAA Jacksonville FL Office: Watches - Warnings - Advisories
FL...None. GA...None. AM...None.