Tropical Waves

A central Atlantic tropical wave is near 40W from 14N southward, and moving westward at 10 to 15 kt. Scattered moderate convection is seen from 05N to 08N between 38W and 43W.

Another central Atlantic tropical wave is near 52W from 11N to southward, and moving westward at 10 to 15 kt. Scattered moderate convection is present from 01N to 08N between 50W and 61W, including French Guiana and Suriname.

A southwestern Caribbean tropical wave is near 78W from 14N southward across eastern Panama into the Pacific Ocean. It is moving westward at 10 to 15 kt. Convection associated with this wave is mentioned in the Monsoon Trough/ITCZ section below.

Monsoon Trough/ITCZ

A monsoon trough enters the Atlantic along the Senegal coast near Dakar, then curves southwestward to 03N24W. An ITCZ continues westward from 03N24W to 01N37W. Scattered moderate convection is noted south of the monsoon trough from 03N to 10N east of 17W. Widely scattered moderate convection is noted north of the ITCZ from 02N to 06N between 25W and 37W.

The eastern end of the East Pacific monsoon trough is triggering numerous heavy showers and isolated strong thunderstorms across the Caribbean waters near Costa Rica and Panama.

Gulf Of America

A pronounced upper-level trough across the western Gulf is combining with abundant tropical moisture to produce scattered heavy showers and strong thunderstorms with locally gusty winds and rough seas at the southwestern and central Gulf. Otherwise, weak ridging across the northeastern Gulf and northern Florida is supporting gentle to moderate SE to S winds and seas of 3 to 6 ft for the entire Gulf.

For the forecast, the ridge will sustain moderate to locally fresh SE to S winds through Fri, then diminish to between gentle and moderate over the weekend. The exception will be evening pulses of fresh winds off the northern Yucatan through this weekend. Scattered heavy showers and strong thunderstorms will persist at the southwestern and central Gulf until this evening, then the eastern Gulf tonight and Fri. Frequent lightning with gusty winds and locally rough seas are expected in strong thunderstorms. Mariners are urged to keep up to date with the latest forecasts.

Caribbean Sea

The southeastern end of an upper-level trough near the Yucatan Peninsula is enhancing scattered showers and isolated thunderstorms off the coast of Nicaragua and in the Gulf of Honduras. Refer to the Monsoon Trough/ITCZ section for additional convection in the Caribbean Sea. Strong to near-gale E winds and seas of 9 to 11 ft are noted at the south-central basin, while fresh to strong E winds with 6 to 8 ft seas are evident at the north-central and part of the southwestern basin. Gentle to moderate NE to SE winds and seas at 4 to 6 ft dominate the lee of Cuba and waters near Costa Rica and Panama. Moderate to fresh E to SE winds and 5 to 7 ft seas prevail for the rest of the Caribbean Sea.

For the forecast, the tight pressure gradient between a 1020 mb high in the western Atlantic and a 1006 mb Colombian low will continue to support fresh to strong trades and rough seas across the central Caribbean through this evening before gradually diminishing in areal coverage late tonight through Fri. Winds are expected to pulse to near-gale force off northwestern Colombia this morning and then this evening. Trades in the Gulf of Honduras and just north of Jamaica will reach fresh to locally strong early this morning, and then tonight. The aforementioned high is going to weaken and open up into a ridge near 24N by Fri. This will yield moderate to locally fresh winds and moderate seas across most of the basin through the weekend, except the south- central basin, where fresh to strong winds and rough seas will remain.

Atlantic Ocean

An Atlantic Ridge stretching west-southwestward from 1024 mb high near Madeira across 30N30W to a 1020 mb high north of Leeward Islands near 25N63W is promoting gentle with locally moderate winds and 4 to 6 ft seas in mixed moderate swells north of 22N between 35W and the central Bahamas/Florida coast. For the tropical Atlantic from 06N to 22N between 35W and the southeast Bahamas/Lesser Antilles, moderate to locally fresh NE to E winds and seas at 6 to 8 ft are seen. Gentle to moderate E to SE winds and 4 to 6 ft seas in mixed moderate swells prevail elsewhere in the Atlantic Basin west of 35W.

For the forecast west of 55W, the aforementioned Atlantic Ridge will support gentle to moderate winds with moderate seas south of 28N into nearly next week. For the waters north of 28N and east of 70W, two cold fronts migrating eastward across the north Atlantic is going to bring fresh to strong winds along with rough seas tonight through Fri evening, then again from Sat night through Sun night.

Posted 4 hours ago by NHC Forecaster Chan