Monsoon Trough Itcz

The monsoon trough reaches the Atlantic through the coast of Liberia near 06N09W and continues southwestward to 02N16W. The ITCZ extends from 02N16W to 02S43W. Scattered showers are along the ITCZ and monsoon trough.

GULF OF AMERICA,

A new cold front extends from SE Louisiana to NE Mexico. Fresh to strong NE winds and building 4-6 ft seas follow the front in the NW Gulf. Scattered moderate convection is from 24N to 28N west of 94W, and within 120 nm ahead of the remainder of the front. Elsewhere, the diurnal trough is analyzed in the Bay of Campeche, and weak troughs are analyzed in the E Gulf and inland over the Florida Peninsula. Scattered showers are near these troughs. Gentle to moderate trades, and 2-4 ft seas, prevail across the waters ahead of the front.

For the forecast, the aforementioned cold front will reach from near Apalachicola, Florida to 26N95W and to 19N95W by this evening, then slow down as it reaches from near Tampa to 26N92W and stationary to 18N94W Mon afternoon, from southwest Florida to 25N90W to 24N94W and stationary to 18N94W late Mon night, then stall and perhaps linger into most of Thu. Scattered showers and thunderstorms, some with gusty winds, are expected near the front. Fresh to strong northeast northeast winds and rough seas will develop behind the front across portions of the western Gulf into Mon, then similar conditions will materialize over the NE Gulf Tue through Thu. Near gale, to at times gale, conditions are possible near Florida Wed and Wed night.

CARIBBEAN SEA,

The pressure gradient between subtropical Atlantic high pressure and the Colombian low continues to support fresh to locally strong trades offshore Colombia. Seas are analyzed to be 7-9 ft, per the latest satellite altimeter data received for the region. Elsewhere, moderate to fresh trade winds and 4-7 ft seas are noted in the eastern and central basin, and gentle trades with 2-4 ft seas are analyzed in the western basin. Scattered moderate convection is apparent across the southern Windward Islands.

For the forecast, high pressure north of the basin will shift eastward through Mon allowing for pulsing strong winds and rough seas offshore Colombia to diminish. A trough just north of Hispaniola will drift west-northwestward toward the Bahamas through Tue. The gradient between it and central Atlantic high pressure will maintain fresh trade winds across the eastern Caribbean, with gentle to moderate winds elsewhere. Trades may increase again in the south-central Caribbean beginning during the middle part of the week as a new and stronger area of high pressure builds southward over the western Atlantic in the wake of a cold front.

ATLANTIC OCEAN,

Areas of high pressure centered near the Azores and Bermuda are dominating the basin. Satellite scatterometer data indicates moderate to fresh trades north of 18N west of 50W, across most of the western Atlantic offshore zones. Seas have built to 8-10 ft from 18N to 28N between 60W and 76W, including along the eastern islands of the Bahamas and Turks and Caicos. Scattered showers are also affecting these waters. Elsewhere across the tropical Atlantic, trades are moderate or weaker with 4-7 ft seas in open waters.

For the forecast west of 55W, fresh to strong east winds and rough seas E of the Bahamas and N of Hispaniola and Puerto Rico will gradually decrease into Mon as Bermuda high pressure moves E and weakens. In the wake of the high, a cold front will move off the SE U. S. coast early Mon, then slide slowly eastward through early week. As it does, a westward moving inverted trough N of Hispaniola will likely interact with the front and low pressure may form as a result along the front in the vicinity of the Bahamas. Any low that forms will track northeastward along the frontal boundary, then N of the region Wed into Thu. The pressure gradient between the low pressure and high pressure building in to the SE U. S. will lead to widespread strong to near gale-force northeast winds N and W of the cold front Tue through late week, along with very rough seas. Mariners are advised to keep up with the latest forecast and stay informed abreast for possible gale conditions developing as early as Tue.

Posted about 3 hours ago by NHC Forecaster Mahoney