Monsoon Trough/ITCZ

The monsoon trough axis enters the eastern Atlantic through the southern Guinea-Bissau coast near 12N16W and continues southwestward to 04N23W, where it transitions to the ITCZ. The ITCZ then continues southwestward to the coast of Brazil near 01N48W. Scattered moderate and isolated strong convection is occurring from the Equator to 08N between 00W and 17W. More scattered moderate convection is occurring within 150 NM of both the monsoon trough and ITCZ between 17W and 35W.

A portion of the East Pacific monsoon trough enters the SW Caribbean near 10N83W and extends to the Colombia Low analyzed near 10N76W. Scattered moderate and isolated strong convection is observed in the SW Caribbean S of 11N.

Gulf Of America

A diurnal surface trough is analyzed from 25N94W southwestward to near Veracruz, Mexico. Winds across much of the Gulf are from the E to SE and sustained at moderate to fresh speeds, with fresh to locally strong ESE winds occurring to the east of the trough per recent scatterometer data. Seas are 3-6 ft across the majority of the basin, with 1-3 ft seas closer to the coasts of Florida, Alabama, and Mississippi, as well as near the coast of the Yucatan Peninsula.

For the forecast, a ridge will continue to dominate the Gulf waters this week. Its associated gradient will maintain moderate to fresh east to southeast winds over the basin for the next few days. East winds will pulse to strong speeds north of the Yucatan peninsula and over the Bay of Campeche at tonight through Fri night in association with a diurnal trough. Moderate to fresh east winds and moderate seas are expected over the Straits of Florida through Thu night. Winds elsewhere will begin to diminish Fri and into the weekend. Looking ahead, a weak cold front may reach the NE Gulf Sat night.

Caribbean Sea

Aside from the convection mentioned in the Monsoon Trough/ITCZ section, upper level troughing extending across the central to eastern Caribbean supports scattered showers across areas E of 74W. Recent scatterometer data indicate moderate to fresh E to NE winds prevailing across the central and W Caribbean, with gentle to moderate trades elsewhere in the basin. Seas are 3-6 ft across the basin, locally up to 7 ft off the NW coast of Colombia.

For the forecast, high pressure north of the basin combined with the Colombian Low will support pulsing fresh to strong trades at night over the Windward Passage and south of Cuba through Thu night. Elsewhere, rather quiet conditions are expected over the forecast waters through the weekend.

Atlantic Ocean

A cold front enters the discussion waters near 31N51W and extends southwestward to 26N58W where it becomes a stationary front. The stationary front then continues southwestward to 21N68W. A pre- frontal trough is analyzed from 27N55W southwestward to the Leeward Islands. Scattered moderate convection is observed ahead of both of these features, in a region N of 25N between 48W and the cold front. Scattered showers are also observed in the vicinity of these features. Winds behind the front are from the NE and sustained at moderate to fresh speeds, with seas behind the front analyzed at 4-8 ft. NE winds are fresh to strong between the Bahamas and Cuba, including through the Florida Straits. Winds across areas from the front eastward to about 45W and N of 17N are from the SE, sustained at moderate to locally fresh speeds and accompanied by by seas of 4-7 ft.

The remainder of the tropical and subtropical Atlantic is under the influence of ridging stemming from a pair of highs north of the area. Fresh to locally strong E to NE winds and seas of 8-12 ft prevail across a region N of 17N between the W coast of Africa and 45W, except for areas between the Canary Islands and Africa where seas are 4-8 ft. Moderate to fresh E to SE winds and moderate seas prevail across the Atlantic S of 17N.

For the forecast west of 55W, a stationary front extending from 31N52W to 21N68W will begin to weaken Thu. A surface trough is just ahead of the front and extends from 27N55W to near Guadeloupe in the Lesser Antilles. High pressure west of these features will remain about stationary through Thu, then begin to shift eastward into the weekend. The front and trough are forecast to merge near 55W on Thu. A weak low may develop along the trough axis on Fri. This will induce fresh northeast winds north of 27N and east of 65W from Fri morning into the weekend. Looking ahead, a weak cold front may emerge off the U.S. Southeastern coast late Sat night into Sun.

Posted 35 minutes ago by NHC Forecaster Adams