Special Features

Central Atlantic Gale Warning and Significant Swell: A 994 mb low pressure is centered well NE of Bermuda near 38N51W. A broad area of low pressure extends from this low southward to near 24N. Ahead of the low, a cold front stalls near 30N40W and then continues SW to the northern Leeward Islands. The pressure gradient between the front and strong high pressure building across the Bahamas offshore waters continue to support gale-force WNW winds N of 30N between 47W and 56W. However, fresh to near gale-force W to NW winds extends to 26N and westward to about 65W. Ahead of the front, winds are fresh to strong from the SW and extend southward to 25N and eastward to 32W. Sofar buoys in the region show wave heights as high as 25 ft N of 26N ahead of the front and 12 ft seas in long period NW swell reaching as far south as 20N. The area of gale force winds will lift north of the area overnight as the low pressure shifts northeastward. However, the broad area of combined seas in excess of 12 ft will gradually subside through Wed evening from west to east. 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 northern Caribbean will tighten the pressure gradient across the basin. This will result in increasing NE winds over the central and SW Caribbean, forecast to reach gale-force speeds offshore Colombia at night tonight and again Tue night. Seas will build 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 enters the Atlantic through the coast of Liberia near 06N10W to 02N29W. The ITCZ continues from 02N30W to 01S47W. Scattered moderate convection extends from 00N to 06N between 08W and 33W, and from 01S to 04N between 37W and 51W.

Gulf Of America

A surface ridge extends across the entire Gulf, anchored by a 1027 mb high pressure centered over coastal North Carolina. This pattern is maintaining light to gentle breezes and slight to moderate seas, except for moderate to fresh NE winds off the Yucatan Peninsula into the Bay of Campeche and SE winds of same speed over the E Mexico and Texas offshore waters.

For the forecast, high pressure will generally dominate the Gulf waters through late week, bringing a gentle to moderate mainly southerly flow. Locally fresh winds are expected, mainly at night, just west of the Yucatan Peninsula, and over the far western waters. Slight to moderate seas will prevail. Looking ahead, southerly winds may increase this weekend ahead of an approaching cold front.

Caribbean Sea

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

High pressure over the Gulf of America is building southeastward over the NW Caribbean, which is acting to increase NE winds over the western and central Caribbean to fresh to strong speeds. Moderate to locally fresh NE winds are elsewhere over the E Caribbean. Seas basin-wide are moderate, except rough to 9-10 ft south of Hispaniola, across the NE Caribbean Atlantic passages, and offshore Colombia.

For the forecast, high pressure over the western Atlantic combined with the Colombian/Panamanian low will support fresh to strong winds across most of the central Caribbean, including the Windward Passage, and the waters between Cuba and Jamaica through Wed. Winds will pulse to gale-force tonight and again Tue night offshore Colombia. Meanwhile, large NW to N swell will impact the Mona Passage, Anegada Passage, and tropical N Atlantic waters into Wed creating hazardous marine conditions.

Atlantic Ocean

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

Hazardous marine conditions dominate much of the central subtropical basin, as described in the Special Features section, in association with a large and deep low pressure system moving northeastward across the northwest Atlantic. A cold front extends from the Azores to near 30N40W where it stalls and continues SW to the northern Leeward Islands. High pressure of 1027 mb over coastal North Carolina extends a ridge SE across the Bahamas and adjacent offshore waters. To the east of the front, a 1026 mb high pressure just NW of the Canary Islands extends a ridge to 43W. Aside the conditions described in the Special Features for the central Atlantic, long period NW swell in the wake of the front continue to affect the offshore zones E of the Bahamas with rough to very rough seas to 21 ft. Ahead of the front, over the far E subtropical Atlantic, seas are 8 to 11 ft.

For the forecast west of 55W, the stationary front will slowly dissipate into Wed. Gale-force winds in the far NE waters will end by Tue morning, with winds decreasing basin-wide as high pressure moves E into the region. Very rough seas E of 72W will slowly subside from W to E, finally decaying below 12 ft in the NE waters Tue night. Fresh to strong SW winds and building seas will commence Wed N of 28N, ahead of another cold front that will enter the region Thu.

Posted 38 minutes ago by NHC Forecaster Ramos