Special Features

Central Atlantic Significant Swell: A large area of strong E winds and seas of 9 to 12 ft extend across the central Atlantic from 19N to 29N, E of 55W. These conditions are being generated by a pressure gradient between Azores high pressure and a robust surface trough that extends along 55W from 07N to 25N. The highest seas are associated with near gale-force winds in a corridor near the apex of the trough, from 22N to 26N between 45W and 55W. The trough will continue to move to the W-NW at 20 kt and pass north of the Leeward Islands by mid week. Winds will diminish slightly through the period, but given the long fetch and duration of the winds, this pattern will support seas building to 12 to 13 ft through today over an area from 22N to 28N between 45W and 58W. Winds will be moderate to fresh by Wed, but 8-10 ft seas will persist across tropical Atlantic waters east of 60W through late week.

Monsoon Trough Itcz

The monsoon trough enters the eastern Atlantic near 12N16W and continues to 09N18W. The ITCZ extends from 09N18W to 05N25W to 07N52W. Scattered moderate convection is depicted from 05N to 07N between 20W and 30W.

GULF OF AMERICA,

A stationary front extends from near New Orleans, Louisiana, to just south of the mouth of the Rio Grande. Strong NE winds and 6 to 8 ft seas follow the front over the far northwest part of the Gulf. A few showers are evident along the front. A surface trough remains in place over the central Gulf along 88W from 23N to 27N. Gentle to moderate breezes and 3 to 5 ft seas are noted elsewhere across the Gulf.

For the forecast, winds and seas behind the front will diminish today. The front is expected to remain stationary over the northern Gulf into Tue, when a low pressure will form off Texas and move NE across the SE U. S. into the NE Atlantic. Winds will increase to strong speeds in the NE Gulf Mon night and diminish on Tue. Thereafter, the front will move southeastward farther into the basin, but then stall again over the central Gulf through mid- week, as another low forms over South Texas. Looking ahead, expect fresh southerly flow over the western Gulf as the low pressure moves northeastward.

CARIBBEAN SEA,

A few showers and thunderstorms are active over the northern Windward Passage, associated with an upper trough in the area. Low level trade wind convergence along with modest upper level divergence is also supporting a few thunderstorms off eastern Panama. High pressure north of the area over the western Atlantic is supporting moderate to fresh trade winds and 4 to 6 ft seas east of 80W. Gentle to moderate NE breezes and 2 to 4 ft seas are noted elsewhere.

For the forecast, high pressure centered north of the Caribbean Sea will support moderate to fresh trade winds across most of the basin through the forecast period. Winds and seas will lessen a bit on Tue as the high pressure departs eastward, but another ridge will build in soon thereafter.

ATLANTIC OCEAN,

Please see the Special Features section for information on Significant Swell in the Central Atlantic.

A dissipating stationary front extending from 31N60W to 25N73W is followed by fresh to locally strong NE winds and moderate to locally rough seas. A recent scatterometer satellite pass also confirmed fresh to strong E winds across the Turks and Caicos Islands and near the northern entrance to the Windward Passage. This may be in-part related to scattered showers and thunderstorms in that region associated with an upper trough extending along 70W. Scattered showers and thunderstorms are also noted farther north ahead of the trough, covering the area from 24N to 30N between 60W and 70W. Farther east, as discussed in the Special Features section, a surface trough extends along 55W from 07N to 25N, moving west at 15 to 20 kt. Aside from the winds and seas described in the Special Features section, moderate to fresh breezes and 5 to 7 ft seas prevail across the basin.

For the forecast west of 55W, the stationary front will dissipate overnight, and high pressure north of the front will shift eastward, allowing winds and seas to diminish. Another weak front will stall off the northeast Florida coast by Mon, then lift northward Mon night. Expect fresh to strong southerly winds and building seas north of 28N and west of 74W late Mon and Tue as low pressure moves from the northern Gulf to the Carolinas. Looking ahead, these southerly winds will shift eastward Tue night into Wed, north of 28N ahead of a cold front moving off the northeast Florida coast Tue night. This front will reach from near Bermuda to South Florida on Wed, and from 31N60W to central Cuba by late Thu. Meanwhile, strong winds and rough seas will accompany a trough moving westward into the waters NE of the Leeward Islands through Tue. Then, the trough will pass just N of Puerto Rico on Wed.

Posted about 1 hour ago by NHC Forecaster Christensen