Monsoon Trough Itcz

A monsoon trough enters the Atlantic along the coast of Senegal near 14N16. 5W then curves southwestward to 02. 5N33W. ITCZ continues southwestward from 02. 5N33W to 01N38W to 07N56W and then to the coast of Guyana near 07N59W. Numerous moderate scattered strong convection is noted south of the monsoon trough from 00N to 07N between 09W and 25W. Scattered moderate convection is seen near and up to 150 nm within the ITCZ west of 46W.

Gulf Of America

The remnants of the recent cold front can be seen in satellite imagery this evening, in the form of a shearline, extending from offshore the NW coast of Cuba near 23N84W to 24N89W to 27N94W. Midday satellite scatterometer wind data showed convergent fresh to strong E to SE winds to the northeast of this boundary, that continue to trigger scattered showers and thunderstorms within 200 nm NE of the shearline, and extend inland across the coasts of Louisiana and southeast Texas. Seas are 5 to 8 ft within these winds. Otherwise, high pressure across the western Atlantic extends a ridge southwestward over the Gulf. Gentle to moderate SE to S winds with 3 to 5 ft prevail across the W and SW Gulf.

For the forecast, fresh winds and rough seas along and just NE of the shearline will gradually diminish tonight in the southeastern and central Gulf. High pressure will then build across the Gulf region, with a relatively weak pressure gradient expected across the area. This will result in gentle to moderate SE winds basin- wide Thu through the weekend.

Caribbean Sea

The tail-end of an old cold front has become stationary across the N and NW coast of Hispaniola, and is producing scattered showers across eastern Cuba, along the north coast of Hispaniola, and across interior Jamaica. Farther west, a surface trough is bringing patchy showers in the northwestern basin. Moderate to locally fresh ENE winds and seas of 4 to 6 ft prevail in the lee of Cuba and through the Windward Passage. Gentle to moderate ENE to E winds and 2 to 4 ft seas prevail across the remainder of the Caribbean Sea, except seas to 5 ft along the NW coast of Colombia.

For the forecast, fresh to locally strong NE winds are expected through the Windward Passage and southwest of Cuba through tonight as a late-season cold front stalls across eastern Cuba and the N coast of Hispaniola along about 20N, then dissipates Thu. The Atlantic high pressure located north of the basin will weaken over the next couple of days and support a weaker than usual pressure gradient over the Caribbean Sea into the weekend. This will result in mainly gentle to moderate winds and slight to moderate seas across the entire basin Fri through Sun.

Atlantic Ocean

An Atlantic cold front enters the area waters near 31N53W and extends southwestward to 21N67W, then has become stationary to the NW coast of Haiti. Scattered showers and isolated thunderstorms are occurring up to 300 nm E of the front, to the N of 25N, and within 90 nm southeast of this feature elsewhere. Further south, a surface trough is causing scattered showers east of the northern Leeward Islands. Fresh to locally strong N to NE winds and 7 to 11 ft seas prevail N of the cold front, except gentle to moderate winds and seas at 3 to 5 ft off northeastern Florida to 75W. To the east of the front, moderate S to SW winds and 4 to 6 ft seas dominate north of 25N between 44W and cold front. For the remainder of the Atlantic west of 36W, gentle with locally moderate ENE to E winds and 4 to 5 ft seas exist. N of 20N and E of 36W, N swell is producing seas of 7 to 12 ft, with new large N swell poised to enter those waters and reinforce seas tonight and Thu.

For the forecast west of 55W, fresh to strong N to NE winds and rough seas will follow the front as it moves eastward through tonight, and stalls along about 20N to the north of Puerto Rico and Hispaniola. Conditions will gradually improve late this week as the front weakens and eventually stalls Fri over the SE waters. High pressure in the wake of the front will weaken over the next couple of days, bringing a gentle to moderate anticyclonic flow with slight to moderate seas through the weekend, with the exception of the NE waters where fresh westerly winds and rough seas are expected as a cold front clips the area on Sat.

Posted about 3 hours ago by NHC Forecaster Stripling