Tropical Waves

A eastern Atlantic tropical wave is along 21W, south of 16N, moving W at 5 to 10 kt. Scattered moderate convection is noted from 06N to 10N and east of 24W.

A central Atlantic tropical wave is along 53W, south of 15N, moving westward at 15-20 kt. Scattered moderate convection is present from 09N to 12N between 51W and 57W.

A Caribbean tropical wave is along 83W, south of 20N, moving westward at 15 to 20 kt. Scattered moderate convection is occurring S of 12N and W of 80W, likely enhanced by the Eastern Pacific monsoon trough extending through the region.

Monsoon Trough/ITCZ

The monsoon trough enters the Atlantic through the coast of Mauritania near 21N17W and continues southwestward to 06.5N35W. The ITCZ extends from 06.5N35W to 09N52W. Scattered moderate convection is evident from 05N to 11N and between 24W and 42W.

Gulf Of America

Weak high pressure dominates the Gulf waters, supporting moderate or lighter winds and slight seas across the basin. Divergence aloft is producing a few showers and isolated thunderstorms over the Bay of Campeche as well as the NE Gulf.

For the forecast, a weak surface ridge will dominate the basin through the forecast period. Fresh to strong NE to E winds will pulse off the NW Yucatan Peninsula nightly through early next week due to local effects associated with a daily surface trough. Gentle to moderate easterly winds will prevail across the western half of the Gulf while moderate or lighter winds are expected elsewhere E of 90W.

Caribbean Sea

Any convection in the SW Caribbean is described in the Tropical Waves section above.

A tight pressure gradient between the subtropical ridge across the Atlantic and lower pressures in northern Colombia supports fresh to locally near gale-force easterly trade winds and seas of 8-12 ft in the central to SW Caribbean. The strongest winds and highest seas are found off NW Colombia. Moderate to fresh easterly winds and moderate seas are occurring in the eastern Caribbean. Elsewhere, moderate or lighter winds and slight to moderate seas prevail.

For the forecast, the pressure gradient between the subtropical ridge north of the islands and the Colombian Low will support fresh to strong trade winds and moderate to rough seas over the central Caribbean through Fri morning, then diminish slightly through the weekend. Expect winds to reach near-gale force each night offshore of Colombia and in the Gulf of Venezuela. Otherwise, moderate to fresh trades will continue in the eastern Caribbean while moderate or weaker winds will prevail over the NW part of the basin. Active showers and thunderstorms are expected across the SE Caribbean Thu night through Fri night as an upper- level trough sinks across the basin.

Atlantic Ocean

A surface trough extends from 31N74W to the NW Bahamas, aiding in the development of scattered moderate convection between the NW Bahamas and SE Florida. Similar convection is occurring north of 27N and between 50W and 65W. A 1034 mb high pressure system centered NE of the Azores extends a ridge southwestward to the waters east of the Bahamas. Moderate to fresh easterly winds and seas of 4-8 ft are found south of 24N and west of 35W. Moderate to fresh N-NE winds and seas of 5-8 ft are present north of 20N and east of 35W. Elsewhere, moderate or lighter winds and moderate seas prevail.

For the forecast west of 55W, a surface trough extends from 31N74W to the NW Bahamas and will gradually dissipate today while drifting northwestward toward the southeastern U.S. Coast. The Atlantic ridge will then build weakly westward into central Florida through early next week. This pattern will support moderate to fresh E-SE trade winds S of 22N, and moderate or weaker winds elsewhere. Expect fresh to strong winds each late afternoon into the early evening hours near the coasts of Hispaniola and Puerto Rico.

Posted 3 hours ago by NHC Forecaster Adams