Special Features

Invest AL92: Showers and thunderstorms are showing some signs of organization along a tropical wave located over the central Atlantic along 38W-39W. An associated 1011 mb low center is located near 11N36.5W. Environmental conditions are forecast to be conducive for development over the next few days and a tropical depression will likely form within a couple of days while the system moves W to W-NW at 10 to 15 kt across the central tropical Atlantic. There is a high chance for tropical formation in the next 7 days.

Tropical Waves

A tropical wave is moving away from the African coast, and is along 21W, moving W at 10 to 15 kt. Scattered moderate isolated strong convection is noted ahead of this wave from 08N to 12.5N between 20W and 24.5W.

See the Special Features section above for information on a tropical wave along 38W-39W. Low pressure near 11N36.5W associated with this wave is likely to develop into a tropical depression over the next couple of days. Scattered moderate convection is noted from 08.5N to 13.5N between 33.5W and 38.5W

The axis of a tropical wave is along 59W extending southward from 18N, moving west at around 20 kt. Scattered moderate convection is noted from 11N to 18N between 56W and 61.5W.

The axis of a tropical wave is along 71W S of 22N, crossing Hispaniola, moving west at around 20 kt. Widely scattered moderate convection is occurring over Hispaniola and the adjacent coastal waters.

The axis of a tropical wave is along 87W, S of 21N, extending through the Gulf of Honduras southward into the far eastern Pacific, moving W at 15 to 20 kt. Scattered to numerous moderate isolated strong convection is noted from 14N to 21N and W of 83W.

Monsoon Trough/ITCZ

The monsoon trough enters the Atlantic near 14.50N17W and extends to 11.5N22W to 1011 mb low pres near 11N36.5W to 10.5N52W. Aside from the convection mentioned in the tropical waves section, scattered moderate convection is noted from 07N to 13N between 24W and 52W.

Gulf Of America

Western Atlantic high pressure extends a ridge along 27N-28N, across Florida and into the N Gulf waters, where a 1019 mb high is found near 27.5N84.5W. A surface trough has moved westward offshore the Yucatan Peninsula and into the eastern Bay of Campeche, and has triggered scattered moderate convection over the eastern half of the Bay of Campeche south of 21N. Light winds prevail across the NE Gulf near the high center, while gentle to moderate E to SE winds and 2 to 5 ft seas are elsewhere.

For the forecast, the current ridge extends across the northern Gulf will change little through Sat before weakening Sun. This pattern will produce mostly gentle to moderate E to SE winds across the basin, with pulses of fresh winds occurring north and west of the Yucatan Peninsula and into the Bay of Campeche each evening and night, as a diurnal surface trough migrates from the Yucatan Peninsula westward across the SW Gulf. Slight to moderate seas are expected through the forecast period.

Caribbean Sea

See the Tropical Waves section above for information on convection impacting the basin.

The pressure gradient between Atlantic high pressure north of the area along 27N-28N and the Colombian low is supporting fresh to strong winds over the central Caribbean south of 17N, with associated rough seas to 11 ft near the coast of Colombia. Fresh to strong NE winds are also funneling through the Windward Passage. Mainly moderate winds and seas prevail over the remaining waters.

For the forecast, the pressure gradient induced by the Atlantic ridge to the north will continue to support fresh to strong trades over the central portion of the basin through Wed night. The ridge will begin to strengthen modestly behind a tropical wave entering the eastern Caribbean Wed night, leading to a significant expansion in coverage of strong trade winds over the central and eastern portions of the basin through Sat. Winds may increase to gale-force offshore of Colombia Fri night and Sat night.

Looking ahead, showers and thunderstorms associated with a tropical wave over the central Atlantic are showing signs of improved organization. Environmental conditions are forecast to become more conducive for development during the next couple of days, and a tropical depression will likely form during the latter half of this week while the system moves westward to west- northwestward across the central tropical Atlantic, and reaches the Lesser Antilles over the weekend.

Atlantic Ocean

See Special Features section above for information on Invest AL92 located over the central Atlantic.

High pressure prevails over the waters N of 18N, anchored by a 1021 mb high centered near 27.5N50W, and extending from 25W to Florida. Mainly gentle winds prevail over the waters N of 23N and west of 25W, with slight to moderate seas. Moderate to fresh trade winds are noted S of 24N, with moderate seas. Overnight satellite scatterometer winds showed broad cyclonic winds between 30W and 40W about Invest AL92, with pockets of winds 20-25 kt. Seas are 5 to 8 ft in this area. Offshore Africa, fresh to locally strong NE winds extend from the Canary Islands to 19N then become moderate across the Cabo Verde Islands. Seas of 5 to 8 ft prevail across this area. Saharan Air continues to dominate much of the basin N of 14N between Africa and 60W.

For the forecast west of 55W, the Atlantic high pressure ridge will sink slightly southward Thu, then change little through Fri night, before weakening over the weekend. Winds will freshen from E to W, and south of 23N early Thu through Sat, behind a tropical wave moving across the Caribbean. Fresh trades N of Hispaniola and in the approach to the Windward Passage will pulse to strong speeds each night. Looking ahead, showers and thunderstorms associated with a tropical wave over the central Atlantic are showing signs of improved organization tonight. Environmental conditions are forecast to become more conducive for development during the next couple of days, and a tropical depression will likely form during the latter half of this week while the system moves westward to west-northwestward across the central tropical Atlantic, and reaches the Lesser Antilles over the weekend.

Posted 1 hour, 8 minutes ago by NHC Forecaster Stripling