Altamaha Sound to Fernandina Beach FL Marine Forecast
|Rest Of Today...Northeast Winds 5 To 10 Knots Becoming East 10 Knots Late In The Afternoon. Seas 2 To 3 Feet With A Dominant Period 10 Seconds. A Light Chop On The Intracoastal Waters.|
|Tonight...Southeast Winds 10 Knots Diminishing To 5 Knots After Midnight. Seas 2 To 3 Feet With A Dominant Period 9 Seconds. Mostly Smooth On The Intracoastal Waters.|
|Tuesday...North Winds 5 Knots Becoming East 5 To 10 Knots In The Afternoon. Seas 2 To 3 Feet With A Dominant Period 9 Seconds. A Light Chop On The Intracoastal Waters.|
|Tuesday Night...Southeast Winds 5 To 10 Knots Becoming Southwest After Midnight. Seas 2 To 3 Feet. Mostly Smooth On The Intracoastal Waters.|
|Wednesday...Northwest Winds 5 Knots Becoming East 5 To 10 Knots In The Afternoon. Seas 1 To 2 Feet. A Light Chop On The Intracoastal Waters.|
|Wednesday Night...Southeast Winds 5 To 10 Knots Becoming South After Midnight. Seas 2 To 3 Feet.|
|Thursday...South Winds 5 Knots Becoming East 5 To 10 Knots In The Afternoon. Seas 2 To 3 Feet.|
|Thursday Night...Southeast Winds 5 To 10 Knots. Seas 2 To 3 Feet.|
|Friday...East Winds 5 To 10 Knots Increasing To 10 To 15 Knots In The Afternoon. Seas 3 To 4 Feet Due To Long Period East Swells. Slight Chance Of Showers.|
| AMZ400: Synopsis for Altamaha Sound GA to Flagler Beach FL out to 60 nm|
857 AM EDT Mon Sep 27 2021
High pressure centered over the southeastern states will gradually weaken as it settles over our waters on Tuesday and Wednesday. A weak cold front is forecast to move southward across our local waters by late Thursday night and Friday. Northeast winds will strengthen in the wake of this front from Friday afternoon through the upcoming weekend. Meanwhile, long period swells from Distant Major Hurricane Sam will enter our local waters beginning late Wednesday or Thursday, with seas possibly reaching caution levels offshore on Friday night and Saturday.
The approximate location of the west wall of the Gulf Stream as of Sep 25, 2021 at 1200 UTC...
- 58 nautical miles east of Flagler Beach.
- 68 nautical miles east of Saint Augustine Beach.
- 81 nautical miles east of Jacksonville Beach.
- 99 nautical miles east southeast of St Simons Island.
| Area Forecast Discussion|
National Weather Service Jacksonville FL
918am EDT Monday September 27 2021
Current forecast is on track. Surface high pressure around 1022 mb was over southeast GA at 13Z, which is expected to transition to offshore of the southeast U.S. coast this afternoon. Subsidence and dry air will maintain sunny to mostly sunny skies today and with the surface high moving offshore, a steady easterly wind will develop along with the east coast sea breeze. Only slight adjustments were made to the winds and temps today and tonight. Not much support for patchy fog late tonight and suspect it will be very localized if it does form.
22am EDT]... Near Term - Through Tonight
Radiational cooling may result in patchy radiational fog formation around sunrise, mostly for locations north and northwest of Alma, GA. Otherwise, a dry and subsident air mass will prevail area-wide for most of this week as surface ridging gradually weakens and settles directly over our region by late tonight. The dry air mass and full sunshine will allow highs to climb to the upper 80s at most inland locations today, with the Atlantic sea breeze developing towards noon and pushing inland through the afternoon hours, keeping coastal highs mostly in the mid 80s. These values are near or perhaps a degree or two above late September climatology. Strong subsidence and a dry air mass will allow inland lows to fall to the lower 60s tonight, with a light onshore breeze this evening keeping coastal lows in the mid to upper 60s.
.SHORT TERM [Tuesday Through Wednesday]... Surface high pressure centered over the mid-Atlantic states will slowly shift to the east-southeast into the Atlantic through Wednesday. Dry and quiet weather continue through mid-week with subsidence and a dry airmass lingering over the region. Temperatures will experience a mild warming trend this week with temps rising above the seasonal average with daily highs in the mid to upper 80s and lower 90s with min temps in the low to mid 60s for inland areas.
.LONG TERM [Thursday Through Sunday]... Surface high pressure begins to our east as a weak backdoor cold front moves into the area from the northeast Friday into Saturday. This front could bring a slight chance for showers with possible isolated thunderstorms Friday into the weekend. Ridging builds back in from the north behind the front bringing another cool, dry airmass to the area for the weekend. The warming trend will come to an end by the end of the week with temperatures dipping down slightly below the seasonal average.
NOAA Jacksonville FL Office: Watches - Warnings - Advisories
FL...None. GA...None. AM...None.