Tropical Waves

An eastern Atlantic tropical wave is near 33W from 15N southward, and moving westward at 15 kt. Isolated moderate convection is observed from 03N to 09N between 28W and 36W.

An eastern Caribbean tropical wave is near 64W from 18N southward. No significant deep convection is noted in association with this tropical wave.

An central Caribbean tropical wave is near 72W from 18N southward into northwestern Venezuela. No significant deep convection is noted in association with this tropical wave.

Monsoon Trough/ITCZ

A monsoon trough enters the Atlantic near 17N16W along the coast of Mauritania, then runs southwestward to 05N40W. An ITCZ continues westward from 05N40W to near 05N50W. Scattered moderate convection is seen from 04N-06N between 43W-51W. Isolated moderate convection is observed from 03N to 09N between 28W and 36W.

The eastern end of the East Pacific monsoon trough is bringing isolated moderate convection across the SW Caribbean waters near Panama.

Gulf Of America

1020 mb high pressure is centered over the NW Gulf near 27N93W. Light to gentle winds and seas of 1 to 3 ft are found across the N-central and E Gulf. Mainly moderate E to SE winds and 3 to 5 ft seas prevail for the rest of the Gulf. No significant deep convection is occurring this afternoon.

For the forecast, the aforementioned high pressure will dominate the basin through early Fri before Atlantic high pressure builds westward across Florida and into the Gulf basin along 27N-28N Fri through Sun. Gentle to moderate anticyclonic winds will generally prevail across the basin during this time, except for fresh to locally strong NE to E winds pulsing off the northwestern Yucatan Peninsula nightly through the weekend, and moderate to fresh SE winds across far northwest portions Fri night. Looking ahead, a weak frontal boundary will sink southward into the NE Gulf Mon night.

Caribbean Sea

A broad Atlantic Ridge across the western Atlantic near 29N continues to sustain a robust trade-wind pattern across much of the Caribbean Basin. An upper-level trough is causing scattered moderate convection near Jamaica. Refer to the Monsoon Trough/ITCZ and Tropical Waves sections for additional convection in the Caribbean Sea. Strong NE to E winds and seas of 9 to 12 ft are present over the SW part of the basin, while fresh E winds along with 5 to 7 ft seas dominate the central part of the basin. Moderate to locally fresh E winds and seas at 4 to 6 ft prevail over the Gulf of Honduras. Gentle to moderate NE to E winds and 3 to 4 ft seas are found at the NW basin. Moderate to fresh trades and seas of 5 to 6 ft prevail elsewhere in the Caribbean Sea.

For the forecast, the pressure gradient between the aforementioned ridge and the Colombian low will support fresh to strong trade winds, and rough seas in the south-central basin through tonight, before expanding northward to near 18N Thu morning through Sat morning. Expect winds at near-gale force offshore of Colombia during the nighttime and early morning hours, with gale-force winds likely S of 13.5N Fri night. Pulsing fresh to strong winds and moderate to locally rough seas are expected in the Gulf of Honduras nightly through Sat night. Fresh trades with rough seas should persist east of the Lesser Antilles through midday Thu, diminishing to moderate winds and seas thereafter through Sun.

Atlantic Ocean

A stationary front extends from 31N77W to the Florida-Georgia border with winds on either side of the front being gentle to moderate. Farther east, an vigorous upper-level low near 29N65W is triggering scattered moderate convection from 25N to 31N between 61W and 68W. Refer to the Monsoon Trough/ITCZ and Tropical Waves sections for additional convection in the Atlantic Basin.

Moderate SW winds and seas of 3 to 5 ft are noted east of Florida, north of 28N between 69W and 75W. Otherwise, a broad ridge extending west-southwestward from the central Atlantic to the NE Bahamas is supporting gentle to moderate E to SE winds and 3 to 6 ft seas north of 22N between 35W and the east coast of Florida. For the tropical Atlantic south 22N between 35W and the Lesser Antilles, gentle to moderate with locally fresh NE to E trades and seas at 6 to 8 ft exist.

For the forecast west of 55W, the aforementioned ridge will dominate the western Atlantic through the weekend. Scattered showers and isolated thunderstorms with strong gusty winds will continue across the waters offshore of Florida and the NW Bahamas through Thu, along and SE of a stalled front and pre-frontal surface rough across the NW zones. Fresh to strong easterly winds with locally rough seas are expected near the northern coasts of Hispaniola and Puerto Rico each late afternoon through night through Fri night. Otherwise, moderate to locally fresh trade winds and moderate seas are expected south of 22N through Fri. A N to S aligned surface trough across the central Atlantic will shift westward across the region early Fri through late Sat, reaching 70W Sun morning. This will weaken the ridge and lead to diminishing winds. Looking ahead, a weak cold front will sink southward into the far NW zones off of NE Florida Mon night.

Posted 53 minutes ago by NHC Forecaster Landsea/Rosado-Vazquez