Monsoon Trough/ITCZ

The monsoon trough enters the Atlantic through the coast of Sierra Leone near 07.5N12W and continues southwestward to 04N15W. The ITCZ extends from 04N15W to 01.5N19W to 00.5N40W to the coast of Brazil near 01.5S45W. Scattered moderate isolated strong convection is observed south of 05N between 06W and 37W. Similar convection is noted south of 03.5N and between 40W and 50W.

Gulf Of Mexico

A weak and narrow high pressure ridge extends from the Atlantic near Bermuda southwestward across N Florida and then NW across the NE Gulf of Mexico. This pattern combined with a broad upper ridge building across the basin is producing fair tranquil weather across the basin. Moderate to locally fresh E to SE winds are present from the Straits of Florida to the NW Gulf, where seas are 3-5 ft, and have recently built to 6 ft across the S Texas coastal waters. Light to gentle winds and slight seas are found in the NE Gulf, north of 26N and east of 90E.

For the forecast, Atlantic high pressure extending into the NE Gulf will dominates the basin through Fri. Strong winds will pulse off the northwest Yucatan peninsula during the next several evenings. Winds will become fresh to strong over the western Gulf tonight into Tue. Otherwise, moderate winds and seas will prevail through most of the week.

Caribbean Sea

A surface trough is analyzed in the Caribbean Sea, along 69W. To the west of the trough, scattered showers and isolated thunderstorms have developed from offshore of NE Nicaragua northeastward across Jamaica, Hispaniola, and the Windward Passage. Thunderstorms are more numerous across the mountainous interior of Hispaniola. Generally fair conditions are found elsewhere in the Caribbean.

The pressure gradient between the broad subtropical ridge north of the Greater Antilles and lower pressures in the deep tropics results in strong easterly trade winds in the south-central Caribbean. Seas in these waters are 6-9 ft. Moderate to fresh NE-E winds and seas of 4-6 ft are found in the north-central Caribbean, including the Windward Passage, eastern Caribbean and in the lee of Cuba. Moderate or weaker winds and moderate seas are prevalent in the remaining waters.

For the forecast, fresh to strong trade winds will pulse at night in the SW Caribbean, N of Colombia through the nest few days. Fresh to occasionally strong winds will also pulse in the Windward Passage, S of the Dominican Republic, and in the Lee of Cuba for the next few days. Otherwise, moderate to locally fresh winds and moderate seas can be expected across much of the basin through the middle of the week.

Atlantic Ocean

A stationary front enters the western Atlantic near 31N58W and continues southwestward to eastern Cuba. Scattered showers and isolated mild thunderstorms are evident on satellite imagery within 150 nm W of the frontal boundary. A surface ridge straddles the front, to the north of 30N. A 1027 mb high is centered NE of Bermuda and extends a ridge southwestward to northern Florida. Except for moderate to locally fresh NE winds within 150 nm west of the front, winds are anticyclonic and light to gentle west of the front. Seas are 5-7 ft on both sides of the front, and 2 to 4 ft elsewhere within the ridge.

Farther east, a broad 1007 mb low pressure system is located near 34N31W. Associated scattered convection is occurring N of 31N. Morning scatterometer satellite data showed fresh to strong cyclonic winds north of 28N and between 25W and 40W. Wave heights in these waters are 8-14 ft, with the highest seas occurring near 33N37W. Seas ranging 8 to 10 ft extend as far south as 10N and as far west as 60W. Meanwhile, a trough is noted south of the low along with a cold front spiraling from the northern semicircle to near the Canary Islands. Gentle winds are noted E of 26W to the coast of Africa. Fresh winds are noted S of 22N between 40W and the Greater Antilles.

For the forecast W of 55W, the stationary front will gradually dissipate through Tue. Large N-NE swell across the waters from 65W southward to the Leeward islands will linger through the middle of the week. High pressure will continue to build over waters N of 20N, bringing more tranquil marine conditions.

Posted 5 hours ago by NHC Forecaster Stripling