Special Features

Western and Central Atlantic Gale Warnings/Significant Swell: Recent satellite scatterometer data shows gale force westerly winds continuing N of 28N, between 50W and 67W, occurring behind an Atlantic cold front that extend through 31N43W to just offshore of the north coast of Puerto Rico then westward across Hispaniola. Seas in the area of gales are 20 to 30 ft in W to NW swell, as measured by recent satellite altimeter data, and several Sofar Ocean drifting buoys. Very rough seas in excess of 12 ft extend southward to the southeast Bahamas and to 20N as far W as 74W and southeast of the front to 38W. Generally fresh to strong NW to W winds are ongoing behind the front extending to 24N, with SW winds of similar magnitude ahead of the front. The cold front will move slowly east through through Tue, while weakening, then stall from around 31N38W to 18N56W. Gale-force winds are expected to end early Tue morning, but the NW swell producing very rough seas will persist, gradually subsiding from W to E, but remaining above 12 ft for portions of the waters through Wed. Mariners are urged to stay up to date with the latest forecasts.

South-Central Caribbean Gale Warning: High pressure building southeastward across the western Atlantic and toward the Greater Antilles early this week will tighten the pressure gradient across the Caribbean, to produce increasing NE tradewinds. This will result in gale force winds pulsing tonight and again Tue night offshore of NW Colombia, mainly within about 90 nm from the coast. Seas will build to 9 to 11 ft in association with these gales.

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 details on these events.

Monsoon Trough/ITCZ

The monsoon trough axis enters the Atlantic through the coast of Liberia near 09N09W and extends southwestward to near 02.5N29W, where it transitions to the ITCZ that continues to the coast of Brazil along 00N50W. Scattered moderate isolated strong convection extends from 00N to 04N between 07W and 36W. Scattered moderate convection extends from 00N to 04N between 36W and 50W.

Gulf Of America

High pressure of 1025 mb is centered over the northeast Gulf just offshore of the Florida Panhandle near 29N85.5W, with the associated ridge extending southwestward across the basin and into central Mexico. Thus, winds are anticyclonic, and light to gentle, with some locally moderate E winds across the eastern Bay of Campeche, and across the western Straits of Florida. Seas are 1 to 3 ft, except across the Straits of Florida, where 4 ft seas are occurring.

For the forecast, high pressure will dominate the Gulf waters through late week, bringing gentle to moderate mainly southerly flow. Locally fresh winds are expected, mainly at night, just west of the Yucatan Peninsula, and in southerly flow over the far western waters. Slight to moderate seas will prevail.

Caribbean Sea

See Special Features section above for information on a Gale Warning in effect for waters offshore Colombia.

An Atlantic cold front is moving into the north coast of Puerto Rico and extends westward across Hispaniola. Ahead of it, an old front in the form of a trough extends across the central Leeward Islands to near 14.5N67W. Scattered showers with gusty winds prevail along the trough, and have recently moves ashore across the northern half of Puerto Rico and the north coast of Hispaniola, with the arrival of the front. High pressure is slowly building from the NE Gulf of America southeastward to 65W behind the Atlantic front, and is acting to produce fresh to locally strong NE winds from the south coast of the Dominican Republic to the coastal waters of NW Colombia. Moderate to fresh NE winds prevail across the remainder of the basin W of the surface trough. Seas 3 to 5 ft across NW portions, and 5 to 8 ft within the area of fresh to strong winds. Large northerly swell has reached the Mona and Anegada Passages and is entering into the Caribbean this morning. Elsewhere across the SE part of the basin, moderate E trade winds and seas of 2 to 4 ft prevail.

For the forecast, high pressure will build southward across the basin through tonight, behind the cold front moving across Puerto Rico and Hispaniola. This will lead to increasing trade winds. Fresh NE winds will dominate much of the basin through mid- week, with strong winds developing over the central Caribbean between Hispaniola and Colombia. Winds are likely to pulse to gale- force tonight and again Tue night offshore Colombia. Meanwhile, large NW to N swell will continue to move through the Mona Passage, Anegada Passage, and tropical N Atlantic waters into Wed.

Atlantic Ocean

Please see the Special Features section for details on a gale warning and significant swell in the western and central Atlantic.

Hazardous marine conditions dominate much of the basin, as described in the Special Features section, in association with a large and deep low pressure system moving northeastward across the NW Atlantic, and its associated cold front crossing the central basin. Large NW to N swell is found behind the front to the Bahamas and 77W, and has raced ahead of the front as far E as 25W. Elsewhere, high pressure of 1026 mb centered along the NE Florida coast and extends southeastward to 65W behind the cold front, while 1027 mb high pressure is just W of the Canary Islands and extends a ridge southwestward to 60W. Both of these ridges dominate the remaining waters. Moderate to fresh trades are impacting a belt S of 15N between Africa and the Windward Islands, with seas in this region 5 to 8 ft in N to NW swell.

For the forecast W of 55W, very rough seas impacting waters E of 74W will slowly subside from W to E, falling below 12 ft region- wide by Wed. Peak seas this morning along 31N to the SE of Bermuda will be as high as 32 ft. High pressure will slide eastward across the waters Tue through Thu, leading to mainly improving conditions. Another frontal system passing mainly N of 30N Thu through Fri will lead to strong SW winds N of 29N during that time.

Posted 29 minutes ago by NHC Forecaster Stripling