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Monsoon Trough/ITCZ

The monsoon trough axis enters the Atlantic near the coastal border of Senegal and Guinea-Bissau, then reaches southwestward to 01N26W, and west-northwestward to 01N38W and west-southwestward to near the Amazon River Delta. Scattered moderate to isolated strong convection is from 01N to 03N between 22W-27W, and from 05S to 02S between 26W-31W. Scattered moderate convection is within 60 nm north of the ITCZ between 38W-44W, also within 60 nm south of the ITCZ between 33W-36W and within 30 nm north of the ITCZ between 27W- 35W.

Gulf Of America

A high pressure ridge extends southwestward from a 1019 mb high center that is near the Florida Big Bend area to south of Tampico, Mexico. Moderate to fresh southeast winds are over most of the western half of the Gulf. Seas with these wind are 4 to 6 ft. Latest buoy observations and scatterometer satellite data indicate light to gentle winds in the NE portion of the Gulf, while gentle moderate easterly winds are over the rest of the Gulf, with the exception of moderate northeast to east winds in the far southeastern part of the basin near western Cuba and in the Straits of Florida. Seas in the range of 3 to 5 ft are over the remainder of the Gulf, except for lower seas of less than 3 ft in the NE and eastern Gulf sections.

For the forecast, the aforementioned ridge across the northern Gulf will remain in place and slowly weaken through Sat, maintaining mostly gentle to moderate east to southeast winds across most of the basin. The exception will be off the Yucatan Peninsula, where a daily trough will result in a locally tighter pressure gradient to support a pulsing of fresh to strong winds during the evenings. Fresh to strong north to northeast winds and building seas will follow a cold front moving across the northern Gulf Sat night through the early part of the upcoming week. The front will stall from the Straits of Florida to South Texas by late Mon, then dissipate into mid week.

Caribbean Sea

Water vapor imagery reveals a lingering mid to upper-level trough that extends from the central Atlantic southwestward to across the eastern portion of Hispaniola and continues southwestward to near 13N75W. A surface trough is analyzed from eastern Cuba southward to 16N79W. Abundant moisture east of these features in combination with dynamics aloft related to the mid to upper- level trough is resulting in an unsettled weather pattern for the eastern Caribbean. Scattered showers and isolated thunderstorms along with overcast multilayer clouds are observed east of a line from 18N63.5W to 11N69W. Scattered showers and thunderstorms are north of 15N between 64W and 70W, including the west-southwestern sections of Puerto Rico and over parts of Hispaniola and waters adjacent its eastern and central sections. The unsettled weather conditions will continue for the eastern Caribbean through the weekend.

Moderate to fresh trades are over the eastern Caribbean along with seas of 3 to 5 ft. Mostly gentle trades are over the rest of the basin. Seas are 2 to 4 ft elsewhere in the basin, including the Gulf of Honduras.

For the forecast, A surface trough extending across eastern Cuba and Jamaica will drift slowly westward and weaken through Sat. This feature will disrupt the typical weather pattern across the basin with a weaker than usual pressure gradient. This weaker pressure gradient will support mainly gentle to moderate winds through the remainder of the forecast period. Fresh NE winds may develop early next week across the Windward Passage associated with a late-season cold front moving into Cuba.

Atlantic Ocean

A broad surface trough extends southward from near Bermuda across 31N69W to beyond the central Bahamas and Great Bahama Bank. Isolated weak showers are present from 25N to 30N between the trough and 76W and north of 29N east of the trough to near 67W. Refer to the Monsoon Trough/ITCZ section at the beginning for additional weather in the Atlantic Basin.

The pressure gradient related to high pressure of 1022 mb north of the area at 32N50W is generally providing for light to gentle winds north of 25N between 35W and the Florida/southern Georgia coast. Seas of 4 to 6 ft are within this area of winds as noted in SoFar buoy and altimeter satellite data. Moderate to fresh northeast to east winds and seas of 6 to 8 ft in mixed swell are over the rest of the basin.

For the forecast west of 55W, the aforementioned surface trough will dissipate through Sat. High pressure will build into the area from the east in the wake of the trough. A cold front is forecast to move off the coast of northeast Florida Sun night. Expect fresh to strong north to northeast winds and building seas in the wake of the front as it reaches from near Bermuda to the Florida Straits by late Mon, from near 31N60W to central Cuba by late Tue, before stalling and dissipating along roughly 22N through midweek.

Posted 1 hour, 26 minutes ago by NHC Forecaster Aguirre