Monsoon Trough Itcz

The monsoon trough enters the Atlantic through the coast of Guinea-Bissau near 12N16W and continues southwestward to 05N20W. The ITCZ extends from 05N20W to 00N35W and to 01S49W. Scattered moderate to isolated strong convection is observed south of 03N and west of 30W.

Gulf Of America

A subtropical ridge centered between the United States and Bermuda extends to the Gulf of America, supporting moderate to fresh southerly winds over the western Gulf waters and moderate seas. Moderate to locally fresh easterly winds and seas of 2-4 ft are noted north and west of the Yucatan peninsula. Elsewhere, moderate or weaker winds and slight to moderate seas prevail.

For the forecast, a high pressure ridge extends from the western Atlantic to the central Gulf. The combination of the ridge and broad low pressure over Texas and northern Mexico associated with a trough will lead to a tightening of the pressure gradient over the western and central Gulf waters starting tonight causing moderate to fresh south return flow over those waters through early Fri evening. Looking ahead, that low pressure will pull a cold front over the NW Gulf on Sat afternoon, followed by fresh to near gale north to northeast winds expected Sat night through Sun night. Gale conditions are possible offshore Tampico on Sun and offshore Veracruz Sun afternoon and Sun night. Mariners are urged to stay up to data with the latest forecasts.

Caribbean Sea

A tight pressure gradient between the subtropical ridge north of the Caribbean and lower pressures in NW South America sustain strong to near gale-force NE winds off NW Colombia and the Gulf of Venezuela. This was confirmed by a recent scatterometer satellite pass. Seas in these waters are 6-10 ft. Moderate to fresh easterly trade winds and moderate seas are found in the north-central Caribbean, including the Windward Passage. Moderate to locally fresh easterly breezes and moderate seas are noted in the eastern Caribbean. Elsewhere, moderate or weaker winds and slight to moderate seas are prevalent. A few showers are affecting the Leeward Islands, SE Hispaniola and Jamaica.

For the forecast, the combination of Atlantic high pressure and relatively lower pressure in northern South America will continue to result in fresh to strong northeast to east trades in the south-central Caribbean through the forecast period. Winds may pulse to near gale-force off Colombia at night on Fri and Sat. Fresh northeast winds will pulse in the Windward Passage through Thu. Fresh to strong east to southeast winds will begin to pulse in the Gulf of Honduras Wed evening and continue through Sat night, while trades elsewhere will generally remain moderate to fresh. Additionally, large north swell is expected to impact the tropical N Atlantic waters and the Anegada/Mona Passages beginning on Thu and likely subsiding on Sat.

Atlantic Ocean

A cold front extends from a hurricane-force extratropical low well south of Newfoundland, enters the tropical Atlantic near 31N55W and continues southwestward to 26N63W, where it becomes a stationary front to the NW Bahamas. Numerous moderate to isolated strong convection is noted ahead of the cold front to 51W and north of 24N. Moderate to locally fresh winds and rough seas are found behind these frontal boundaries. Moderate to fresh SW winds and moderate to rough seas are evident ahead of the cold front to 49W and north of 27W.

The remainder of the tropical Atlantic is dominated by a broad subtropical ridge supporting moderate to fresh NE-E winds and moderate to rough seas south and east of a line from 31N25W to the Leeward Islands. The strongest winds and highest seas are found in the deep tropics near 07N45W. Elsewhere, light to gentle winds and moderate seas are present. Saharan dust is evident in the eastern Atlantic.

For the forecast west of 55W, a cold front extending from 31N59W to the N Bahamas this morning will move from 28N55W to the central Bahamas Wed morning, then dissipate by Thu. Fresh to strong SW winds ahead of the cold front north of 29N will pull north of our waters by this evening. In the wake of the front, large to very large N swell will occur with 12 ft or greater seas sliding eastward north of 28N through Wed night. 8 ft seas will progress equatorward reaching 20N by Thu before diminishing on Fri. Winds will become quiescent over forecast waters from Wed through Sat, as a high pressure ridge settles in along 27N. Looking ahead, a strong cold front should emerge from the SE United States coast on Sun, followed by increasing NW winds and building seas.

Posted about 6 hours ago by NHC Forecaster Delgado