Monsoon Trough Itcz

The monsoon trough enters the Atlantic near 06N11W and extends SW to 02N17W to 00N30W. The ITCZ continues from 00N30W to 00N46W. Scattered to locally numerous moderate to strong convection is noted from 07S to 05N between 09W and 39W.

Gulf Of America

Weak surface ridging extends over the eastern Gulf while low pressure dominates the western half of the basin. This is allowing the continuation of gentle to moderate SE winds W of 90W and off the northern coast of the Yucatan Peninsula, and light to gentle winds elsewhere. Slight seas prevail basin-wide.

Shallow low-level moisture interacting with persistent SE flow is supporting areas of dense fog across the NW Gulf. The southeasterly winds are advecting warm, moist air over relatively cooler shelf waters, promoting low-level saturation within a shallow boundary layer. This process is further enhanced by a stable near-surface layer limiting vertical mixing, allowing fog to become dense and widespread at times. Recent satellite imagery, including GOES-19 Night Fog Enhancement, highlights expanding low cloud and fog coverage across the region. In addition, both IFR and LIFR fog probability products indicate a high likelihood of reduced visibilities over the NW Gulf, supporting ongoing observations of dense marine fog.

For the forecast, a ridge across the E Gulf waters, combined with a surface trough along Mexico reaching offshore Veracruz, will support moderate to fresh SE winds and moderate seas over the western half of the Gulf, and gentle to moderate winds with slight to moderate seas over the eastern part of the basin through Thu. In addition, a trough will pulse moderate to fresh winds off the Yucatan Peninsula during the evenings through Thu night.

Caribbean Sea

A large surface trough across the Greater Antilles northern adjacent waters along with a front moving across the NW Atlantic is allowing for a weak pressure gradient across much of the Caribbean, which is supporting gentle to moderate E to SE winds over the SE basin and light to gentle elsewhere, but the NW Caribbean W of 84W where moderate to locally fresh winds are ongoing due to surface high pressure over the E Gulf of America. Slight seas prevail across the basin, except offshore Belize, the Yucatan Peninsula and the Gulf of Honduras where seas are moderate to 4 ft. Otherwise, scattered to isolated showers are occurring over the Lesser Antilles and adjacent waters.

For the forecast, a surface trough located north of the area extending from 24N58W to 21N65W to the Great Bahama Bank near 21N74W along with a front moving across the NW Atlantic will continue to allow a weaker than usual pressure gradient across the central and eastern Caribbean Sea into Mon, thus resulting in mainly moderate or weaker winds and slight to moderate seas, except in the Gulf of Honduras where moderate to fresh E to SE winds will pulse due to nearly stationary high pressure over the E Gulf of America. Winds are forecast to reach moderate to fresh speeds over the east and central Caribbean Mon night through Thu as high pressure builds again N of the area in the wake of the front.

Atlantic Ocean

A cold front extends from 31N52W to 30N55W to 31N63W, which is supporting moderate to fresh SW to W winds N of 29N between 55W and 65W as well as triggering some showers over the central subtropical Atlantic waters. A surface trough extending from 24N58W to 21N65W to the Great Bahama Bank near 21N74W is supporting similar shower activity S of 27N between 55W and the southern Bahamas. Another surface trough is over the E subtropical Atlantic, extending from 31N30W to 25N41W, which is supporting moderate to fresh winds ahead and in its wake along with rough seas to 9 ft. Surface ridging dominates elsewhere, supporting moderate or weaker winds with slight to moderate seas.

For the forecast west of 55W, the surface trough N of the Greater Antilles will remain in place through today and gradually dissipate by Mon. The cold front will continue to support moderate to fresh SW to W winds and rough seas to 9 ft over the NE offshore waters through today. Another cold front is forecast to enter the waters off NE Florida by tonight, extend from near Bermuda to South Florida by Mon night, and from 31N60W to the NW Bahamas by Tue night before dissipating. Moderate to fresh northerly winds and moderate seas are expected N of 27N in the wake of the front.

Posted about 4 hours ago by NHC Forecaster Ramos