Special Features

Western and Central Atlantic Significant Swell:

A cold front extends southwestward from the north-central Atlantic across 31N50W to 28N70W. A new set of large NW swell behind the front is producing 12 to 17 ft seas north of 28N between 50W and 63W. Expect this area of rough to very rough seas to progress eastward through Sat night. Afterward, another set of NW swell will arrive and sustain very rough seas through early next week.

Please read the latest High Seas and Offshore Waters Forecasts issued by the National Hurricane Center at website: https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and https://www.nhc.noaa.gov/marine/offshores.php for more information.

Monsoon Trough/ITCZ

A monsoon trough enters the Atlantic along the Sierra Leone coast near Freetown, then runs southwestward to 06N18W. An ITCZ continues west-southwestward from 06N18W to 03N30W to 01N42W. Scattered moderate to isolated strong convection is observed up to 80 nm along either side of the ITCZ. Widely scattered showers are seen south of the monsoon trough from 04N to 06N between 10W and 16W.

Gulf Of America

A surface trough is triggering widely scattered showers at the western Bay of Campeche. Otherwise, a 1019 mb high over the northeastern Gulf is dominating much of the Gulf with light to gentle winds and 1 to 2 ft seas north of 23N. South of 23N, gentle to moderate NE to E winds and seas of 2 to 3 ft prevail, including the Florida Straits and Bay of Campeche.

For the forecast, a weak pressure gradient will support gentle to moderate E to SE winds and slight to moderate seas across the Gulf through late Sun. The next cold front is expected to enter the northwestern Gulf early Mon, followed by fresh to strong northerly winds and rough seas, except gale conditions will be possible in the far west-central and southwestern Gulf by Mon night.

Caribbean Sea

Convergent trade winds continue to generate scattered showers and isolated thunderstorms at the western Gulf of Honduras, and off the Nicaragua coast. A broad subtropical ridge in the western Atlantic sustains a trade-wind regime across most of the Caribbean Sea. Fresh to strong NE winds and seas of 7 to 10 ft are present at the south-central basin. Moderate to fresh NE to E winds and 4 to 6 ft seas are noted at the north-central and part of the southwestern basin. Gentle to moderate ENE to E winds and seas at 3 to 5 ft prevail elsewhere in the Caribbean Sea.

For the forecast, the pressure gradient between the subtropical ridge and the Colombian low will support fresh to strong winds off Colombia through mid week, with moderate to fresh trade winds elsewhere.

Atlantic Ocean

Please read the Special Features section at the beginning about the ongoing significant swell.

A cold front extends southwestward from the north-central Atlantic across 31N50W to 28N70W, then continues northwestward as warm front to beyond 31N74W. Scattered moderate convection is evident near and up to 80 nm southeast of the cold front east of 54W. Patchy showers are seen up to 50 nm south of the rest of the cold front. At the central Atlantic, convergent southerly winds near a surface trough is triggering scattered moderate convection north of 22N between 37W and 41W. Refer to the Monsoon Trough/ITCZ section for additional convection in the Atlantic Basin.

Outside of the large swell area described in the Special Features section, moderate to fresh with locally strong SW to NW winds and 8 to 11 ft seas are noted north of 25N between 35W and 65W. West of 65W and north of 25N, gentle to moderate with locally fresh SW to W winds and 4 to 8 ft seas exist. To the south from 13N to 25N between 35W and the Bahamas/Lesser Antilles, a broad subtropical ridge is supporting light to gentle winds and 6 to 10 ft seas in large NW swell. For the tropical Atlantic from 00Z to 13N and west of 35W, moderate to fresh NE to E winds with seas at 6 to 8 ft in mixed moderate swell prevail.

For the forecast west of 55W, the cold front will move east of 35W through early Sun. Fresh to strong winds near the front will diminish through tonight. Large N swell following the front will mix with earlier large swell still covering the area east of 65W. Another cold front will move into the waters between northeast Florida and Bermuda by late Sat, and move east of 35W by early Mon, leaving a trailing stationary front to dissipate along 21N. Strong winds and additional large N swell follow this front across waters east of 70W into early next week. A third cold front will move off the northeast Florida coast Mon night, and will reach from Bermuda to Jupiter Inlet, Florida by late Tue, and from 31N60W to central Cuba by late Wed.

Posted 0 minutes ago by NHC Forecaster Chan