Special Features

Western Atlantic Significant Swell: Large NW swell propagating across the western waters is supporting very rough seas of 12 to 16 ft over the waters N of a line from 31N50W to 24N64W to 31N65W. These very rough seas of 12 ft and higher will propagate southeastward through Thu, reaching the waters as far S as 22N and as far E as 45W today, before subsiding below 12 ft tonight.

Central and Eastern Atlantic Significant Swell: Large N-NW swell propagating across the central and eastern waters is merging with easterly trade wind swell across the Tropical Atlantic, which is supporting very rough seas of 12 to 14 ft from 16N to 26N and E of 44W. This swell will continue to spread southeastward over the remainder of the eastern Atlantic waters S of 25N through Thu, but will subside to less than 12 ft by late this afternoon. Very rough seas to near 12 ft will linger over these far eastern waters into the upcoming weekend.

Please read the latest NWS High Seas Forecast issued by the National Hurricane Center at websites: https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more information.

Monsoon Trough/ITCZ

The monsoon trough enters the Atlantic through the coast of Guinea-Bissau near 11.5N15.5W and continues southwestward to 02N21W. The ITCZ extends from 02N21W to the coast of Brazil near 02.5S44W. Scattered moderate to isolate strong convection is observed south of 06N and between 05W and 18W. Scattered moderate convection is noted S of 02N between 28W and 50W.

Gulf Of America

1024 mb high pressure continues offshore of the SW coast of Florida and extends a ridge W-SW to central Mexico. The pressure gradient between the high and lower pressures over Mexico and Texas supports moderate to locally strong southerly winds and moderate seas from the mouth of the Mississippi River to Veracruz. Peak seas have built to 7 ft across the central Texas coastal waters. Moderate to locally fresh NE to E winds and seas of 2-4 ft are noted within 90 nm of the western coast of Yucatan. Elsewhere, light to gentle winds and slight to moderate seas prevail.

For the forecast, the high pressure ridge will shift E-NE across the western Atlantic into the upcoming weekend. This pattern will produce fresh to strong southerly return flow across the NW Gulf today and will expand across the SW and central Gulf this evening into Thu, ahead of the next cold front forecast to enter the NW Gulf Thu night. This weak cold front is expected to sink slowly southward across the north half of the Gulf Fri through Sat night and gradually dissipate.

Caribbean Sea

A stationary front extends from the eastern Dominican Republic to near the Costa Rica-Panams border. A few heavy showers are evident on satellite imagery near this boundary, south of Hispaniola and across the SW Caribbean. The pressure gradient between the aforementioned ridge near Florida and lower pressures associated with the frontal boundary sustain fresh to strong NE winds within 300 nm behind the front. This was confirmed by a recent scatterometer satellite pass, with the strongest winds occurring between Haiti and Jamaica. Seas in these waters are 7-10 ft. Fresh to strong NE winds and moderate seas are found in the south- central and SE Caribbean. Elsewhere, moderate or weaker winds and moderate seas are prevalent.

For the forecast, this front will gradually dissipate today while the strong winds veer NE to E and diminish through Wed evening. Broad high pressure will develop across the central and western Atlantic Wed through Sat and bring a return to fresh to strong trades across the central Caribbean. Meanwhile, rough seas in mixed northerly swell will prevail in the Tropical N Atlantic throughout the next several days.

Atlantic Ocean

Please see the SPECIAL FEATURES section for information about Significant Swell in the western Atlantic, and another Significant Swell in the central and eastern Atlantic.

A weakening cold front extends from 31N54W to eastern Hispaniola. Scattered showers continue along this boundary. Fresh to locally strong S-SW winds and rough to very rough seas to 16 ft in NW swell are occurring ahead of the front to 50W and north of 28N. Behind the front, 1024 mb high pressure is located just east of the NW Bahamas and extends a ridge eastward to the front. Moderate to fresh NE winds and rough seas are present south of 24N and west of the front through the Windward Passage. The remainder of the SW North Atlantic is seeing moderate or weaker winds, and moderate to rough seas in NW to N swell to the W of 67W.

The rest of the central and eastern Atlantic is under the influence of an expansive subtropical ridge centered north of our waters. The pressure gradient between this ridge and lower pressures in the deep tropics and western Africa forces moderate to locally strong and rough to very rough seas over much of the central and eastern Atlantic.

For the forecast west of 55W, the aforementioned front is expected to move slowly southeastward and continue to weaken, stalling from near 29N55W to the Dominican Republic today, before drifting W and dissipating Thu. High pressure will shift NE and into the central Atlantic behind the front today through Thu, and develop a broad ridge across the region that is expected to persist until Sat. A weak front will move off the SE U.S. Coast Sat and move slowly southeastward and weaken through Sun. Meanwhile, seas will gradually subside through Thu night, while seas linger around 8 ft over the SE waters through the end of the period.

Posted 3 hours ago by NHC Forecaster Stripling