Tropical Waves

A tropical wave moving off the coast of Africa was added to the analysis. The tropical wave extends along 21W from 04N-16N, and is moving west at 10-15 kt. Convection is described in the Monsoon trough/ITCZ section below.

An Atlantic tropical wave is near 30N, south of 16N, moving W at 10-15 kt. Convection is described in the Monsoon trough/ITCZ section below.

An Atlantic tropical wave is near 41W, south of 17N, moving W at around 15 kt. Convection is described in the Monsoon trough/ITCZ section below.

A Caribbean tropical wave is near 72W, south of 20N, moving W at at 15-20 kt. Numerous moderate to isolated strong convection is active on the northern end of the tropical wave moving northward toward the Turks and Caicos Islands.

Monsoon Trough Itcz

The monsoon trough enters the Atlantic near 13N17W and continues southwestward to 10N20W. Segments of the ITCZ extend from 09N22W to 08N29W, from 08N31N to 08N40W, and from 07N42W to 07N56W. Scattered moderate convection is active from 05N to 11N between 25W and 45W.

Gulf Of America

1017 mb high pressure is centered near 25N85W. Farther south, a trough reaches across southern Mexico from Chiapas to the Yucatan Channel. Scattered showers and thunderstorms are active off western Cuba on the northern end of this trough. This pattern is supporting moderate to fresh NE winds and 2-3 ft seas off the west coast of the Yucatan Peninsula, and gentle breezes with 1-3 ft seas elsewhere.

For the forecast, the weak surface ridge will continue to dominate the Gulf waters through the forecast period supporting gentle to moderate winds over the western Gulf and light to gentle winds over the eastern Gulf. The exception will be pulsing winds reaching fresh to locally strong speeds off the northwestern Yucatan Peninsula nightly through midweek. These winds are the result of local effects associated with a surface trough. Slight to moderate seas are expected.

Caribbean Sea

The subtropical ridge extending north of the area across the western Atlantic is supporting moderate to fresh trade winds across the eastern and central Caribbean, with strong E winds noted off northeast Colombia and northwest Venezuela. Seas are 4-6 ft. Fresh E winds are noted off the coast of Honduras, but gentle to moderate breezes and 1-3 ft seas are noted elsewhere over the northwest Caribbean. A mid to upper level trough extends from the western Atlantic across eastern Cuba and Jamaica, and toward Nicaragua. Upper level divergent flow along with convergent lower level trade wind flow is support scattered showers and thunderstorms off southern Haiti and northeast Nicaragua. Scattered showers and thunderstorms are also active near the Yucatan Channel near the northern end of a trough reaching across southern Mexico.

For the forecast, the pattern will continue to support fresh to strong trade winds and moderate to rough seas over the central Caribbean through midweek. The aerial extent of these winds will increase Sun night into Mon. Expect winds to reach near-gale force at night offshore of Colombia and in the Gulf of Venezuela from Sun through Wed. Moderate to fresh trades will continue in the eastern Caribbean while moderate or weaker winds will prevail over the NW part of the basin. Otherwise, a tropical wave, with axis along 70W, is generating scattered showers and thunderstorms, more concentrated over the Dominican Republic and its Caribbean waters. The wave and its associated moisture will continue to impact parts of the eastern and central Caribbean, including Hispaniola, the rest of this afternoon and tonight.

Atlantic Ocean

1022 mb high pressure is centered off the central Bahamas near 27N73W. A trough east of this high pressure reaching from 29N64W to 26N70W separates the high pressure from the dominant subtropical ridge which extends from the Azores southwestward toward 25N65W. This pattern is supporting gentle to moderate breezes and 3-5 ft seas along and west of the ridge axis, and moderate to fresh NE to E trade winds and 5-8 ft seas east and south of the ridge axis.

For the forecast west of 55W, the subtropical ridge will continue to build westward across the western Atlantic into central Florida through midweek. This pattern will support moderate to fresh E to SE trade winds S of 22N, and moderate or weaker winds elsewhere. Locally strong winds are likely at night N of Hispaniola, including approaches to the Windward Passage, beginning on Sun.

Posted about 6 hours ago by NHC Forecaster Christensen