Special Feature

Atlantic Significant Swell Event: A cold front extends from 31N47W to 24N57W, where it becomes a stationary front to the Dominican Republic. A recent scatterometer satellite pass captured fresh to strong winds are found north of 27N and between 40W and 60W. Seas of 12-17 ft are present north of 26N and between the front and 65W. Seas of 8-12 ft are noted between 65W and 75W, and also east of the front to 37W and north of 25N. These seas will diminish gradually and decay below 12 ft by late Sat.

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

Monsoon Trough/ITCZ

The monsoon trough is confined to the African continent. The ITCZ extends from 09N17W to 04N33W to 00N50W. Scattered moderate convection is observed from 02N to 07N and between 25W and 49W.

Gulf Of Mexico

High pressure dominates the Gulf of Mexico. Stratocumulus clouds cover most of the basin due to the dry continental airmass filtering southward from the United States. A moderate pressure gradient support moderate to fresh southerly winds and seas of 3-5 ft west of 95W and north of 22N. Moderate to fresh easterly winds and seas of 3-5 ft are found in the Florida Straits. Elsewhere, moderate or weaker winds and seas of 2-4 ft prevail.

For the forecast, high pressure of 1023 mb centered near Jacksonville, FL is spreading surface ridging over the Gulf of Mexico, producing a gentle to moderate anticyclonic flow. The high pressure will shift eastward into the Atlantic tonight, inducing moderate to locally fresh return flow across most of the basin Fri through Sat. A strong cold front is forecast to enter the NW Gulf Sat evening. The front will reach from Mobile, AL to Tuxpan, Mexico Sun morning, from Cedar Key, FL to the central Yucatan Peninsula Sun evening, and exit the basin Mon morning. Strong to gale force winds are expected behind the front, with gale force winds possible across the western Gulf, from offshore southern Texas southward to the Bay of Campeche Sat night through Sun evening. Strong NW gales to near storm-force are possible offshore Veracruz Sun afternoon. A line of strong thunderstorms is likely to accompany the cold front as it moves across the Gulf of Mexico. Winds and seas will gradually subside across the basin late Mon.

Caribbean Sea

A weak stationary front stretches from Haiti to the Bay Islands of Honduras. A few showers are noted near the boundary. High pressure north of the islands sustain fresh to strong trade easterly winds in the south-central Caribbean Sea. These winds were confirmed by a recent scatterometer satellite pass. Seas in these waters are 8-10 ft. The strongest winds and highest seas are found offshore NW Colombia. Fresh to locally strong easterly winds and seas of 5-8 ft are evident in the north-central Caribbean, including the Windward Passage. Moderate to fresh easterly breezes and seas of 4-7 ft are prevalent in the remainder of the basin.

For the forecast, the aforementioned front will remain nearly stationary through Fri while gradually weakening. Fresh NE winds will continue Fri to the NW of the front across the northwest Caribbean, including the Gulf of Honduras. Fresh to strong NE winds in the Windward Passage will continue through Sat night. Strengthening high pressure N of the area will bring an increase in the aerial extent of the fresh to strong trade winds across the central Caribbean during the upcoming weekend, with the strongest winds near the coast of Colombia. Looking ahead, the next cold front will enter the northwest Caribbean late Sun night or early Mon, followed by fresh N to NE winds.

Atlantic Ocean

Please see the Special Features section above for details about very rough seas in the central Atlantic.

The cold front entering the tropical Atlantic near 31N47W is the only feature of interest across the basin, outside of the deep tropics. The front stretches from 31N47W to 24N58W, where it becomes a stationary front to the Dominican Republic. Latest satellite imagery depict shallow convection within 120 nm on both sides of the boundary. For information on the winds and seas associated with this feature, please read the Special Features section. The remainder of the SW North Atlantic (west of 55W) is dominated by a broad subtropical ridge positioned near NE Florida. Moderate to fresh NE winds and seas of 7-10 ft are present south of 24N and west of the front.

The rest of the central and eastern tropical Atlantic is dominated by a 1027 mb high pressure system positioned near Madeira island. The pressure gradient between this ridge and lower pressures in the deep tropics support a broad area of moderate to fresh easterly winds south of 20N and west of 35W. Seas in these waters are 6-9 ft. Similar winds and seas are evident from 17N to 27N and east of 35W. Elsewhere, moderate or weaker winds and slight to moderate seas prevail.

For the forecast W of 55W, the aforementioned front will become stationary on Fri, stretching from 22N55W to the N coast of Hispaniola by Fri afternoon, then will remain nearly stationary along 21N on Sat. Strengthening high pressure N of the area will push the front farther south on Sun reaching the northern Leeward Islands as a dissipating front. The gradient between the strong high pressure along 31N and lower pressure associated with the stalled front will induce fresh to strong NE to E trade winds south of 23N Fri afternoon through Sun. On Sun, fresh to strong southerly flow will set up over the waters east of northeast Florida to about 70W in advance of the next cold front. This cold front is expected to move into the NW forecast waters late Sun, followed by strong northwest winds. Brief winds to gale force appear possible north of 30N near this front, east of northern Florida. Seas will build both east and west of this cold front.

Posted 1 hour, 8 minutes ago by NHC Forecaster Delgado