Monsoon Trough Itcz

A monsoon trough enters the Atlantic through the coast of Sierra Leone near Freetown, then reaches west-southwestward to 06N16W. An ITCZ continues from 06N16W across 04N30W to 04N45W. Scattered moderate to isolated strong convection is seen near these features from 03N to 07N between 10W and 28W, including the coast of Liberia.

The eastern end of the East Pacific monsoon trough is causing scattered showers across the Caribbean waters near eastern Panama and northwestern Colombia.

Gulf Of America

A weakening stationary front meanders westward from near the Florida Keys to the central Gulf, then transitions into a surface trough across the west-central Gulf. Patchy showers are seen near and up to 50 nm south of the front. Two surface trough are triggering widely scattered showers over the north-central and northeastern Gulf. North of the front/trough, gentle to moderate ENE to SE winds and seas at 2 to 4 ft are present. South of the front/trough, a 1019 mb high at the southwestern Gulf is providing light to gentle winds with 1 to 2 ft seas.

For the forecast, moderate to occasionally fresh S to SE winds and moderate seas are expected over the western Gulf through midweek as the aforementioned high builds over the central basin and drifts eastward. Moderate or weaker winds and slight seas will prevail over the rest of the Gulf. Looking ahead, fresh to locally strong S winds and widespread moderate seas will develop west of 90W by Thu, as a complex low pressure system over the central United States strengthens. A cold front associated with this storm system is slated to enter the northern Gulf by next weekend.

Caribbean Sea

A surface trough curves northeastward from the southwest basin through a 1012 mb low near Jamaica to beyond eastern Cuba. Widely scattered showers and isolated thunderstorms are occurring over Jamaica, the Windward Passage and Hispaniola. Moderate to fresh N to NE winds and seas of 4 to 6 ft are present between Jamaica and eastern Cuba. Gentle to moderate with locally fresh N to NE to E winds with 3 to 5 ft seas dominate the southeastern and west- central basin, including the eastern Gulf of Honduras. Light to gentle winds and seas at 1 to 3 ft prevail for the rest of the Caribbean Sea.

For the forecast, moderate to fresh N to NE winds are expected from the north-central through western basin early this week as high pressure over the Gulf of America moves eastward. Elsewhere, moderate or weaker trade winds and slight to moderate seas will prevail over the rest of the basin through midweek. Fresh to locally strong trade winds will develop over the south-central basin by Tue evening, supporting locally rough seas near and to the west of these winds. Looking ahead, widespread fresh trade winds may develop over much of the basin late this week.

Atlantic Ocean

A cold front curves southwestward from the northeast of Bermuda across 31N62W and the central Bahamas to the Florida Straits. Widely scattered showers are noted near and up to 80 nm south of this boundary. To the southeast, a surface trough meanders southwestward from 28N65W across the Turks and Caicos Islands to beyond eastern Cuba. Aided by divergent flows at the mid levels, scattered moderate to isolated strong convection is flaring up near and east of this feature but south of the cold front, north of 20N between 55W and the southeast Bahamas. Refer to the Monsoon Trough/ITCZ section for additional convection in the Atlantic Basin.

Moderate to fresh with locally strong SW to NW to NE winds with 6 to 9 ft seas are found near the cold front, north of 28N between 53W and 76W. To the west and southwest, gentle to moderate N to NE winds and seas of 3 to 5 ft exist east of Florida and across the northwest and central Bahamas. Moderate to locally fresh N to NE winds and seas at 2 to 4 ft are noted near the southeast Bahamas. Otherwise, a broad Atlantic Ridge is dominating waters north of 20N between 35W and 53W, and from 20N to 28N between 53W and 70W with gentle to moderate E to SE to SW winds and 4 to 8 ft seas in mixed moderate swells. For the tropical Atlantic from 05N to 20N between 35W and the Lesser Antilles, moderate with locally fresh ENE to SE winds and 4 to 6 ft seas exist. Gentle to moderate E to SE winds and seas of 3 to 5 ft prevail elsewhere in the Atlantic Basin west of 35W.

For the forecast west of 55W, the aforementioned cold front will drift eastward early this week. Fresh to locally strong SW to W winds and rough seas are expected east of the front, north of 29N, through early Mon morning. Fresh to locally strong N to NE winds and rough seas will occur in the wake of the front tonight, with moderate to fresh N to NE winds and locally rough seas expanding southeastward early this week as high pressure builds to the north. Elsewhere, moderate to fresh S to SW winds may develop offshore of northern Florida by midweek as a surface trough develops to the north. Moderate or weaker winds and moderate seas are expected over the rest of the waters by late this week.

Chan Posted about 2 hours ago by NHC Forecaster