Monsoon Trough/ITCZ

The monsoon trough axis enters the Atlantic near the coastal border of Sierra Leone and Liberia, and continues southwestward to 05N19W, where it transitions to the ITCZ to 02N30W to near 03N46W. Scattered moderate convection is seen within 60 nm south of the ITCZ between 33W and 38W.

Gulf Of America

A cold front extends from the Straits of Florida southwestward to the Yucatan Peninsula and to extreme southern Mexico. High pressure is building across the area behind the front. Fresh to strong winds offshore Veracruz and over the far SW Gulf will diminish to fresh speeds by early this afternoon. Seas of 8 to 10 ft with these winds will subside to 6 to 8 ft in north swell by early in the afternoon. Mostly fresh north to northeast winds are elsewhere southeast of a line from 29N91W to 26N95W and to 20N96W. Seas with these winds are 6 to 8 ft in north to northeast swell.

For the forecast, the aforementioned cold front will stall today from the Straits of Florida to the Yucatan Peninsula. The fresh north to northeast will diminish late tonight into early on Wed as the front weakens further, and at which time light to gentle winds are expected over most of the basin. Seas throughout will subside today. Weak high pressure will slide eastward across the northern Gulf later this week in the wake of a cold front that will be clipping the northern Gulf. Light to gentle winds will be near the high while gentle to moderate winds will be elsewhere over the Gulf. Slight seas are expected for the remainder of the period after today.

Caribbean Sea

A trough is analyzed from near western Cuba to 20N85W and to inland central Honduras. Scattered showers and isolated thunderstorms are noted west and northwest of the trough to the Yucatan Channel and near western Cuba. The pressure gradient between central Atlantic high pressure and relatively lower pressures in northern south America and in the south-central and southwestern Caribbean is generally allowing for moderate to fresh trade winds and seas of 4 to 6 ft to exist east of about 79W. Slightly higher seas of 5 to 7 ft are south of 15N between 64W and 68W. Light to gentle winds along with seas of 2 to 4 ft are over the northwest portion of the basin and near Costa Rica and Panama, including the Gulf of Honduras. Gentle to moderate trade winds with seas of 4 to 6 ft are elsewhere over the sea.

For the forecast, the moderate to fresh trade winds and moderate seas over the central and eastern Caribbean will continue today as weak ridging prevails over the central Atlantic. Winds will begin to pulse to strong speeds in the Gulf of Venezuela and offshore of northern Colombia starting this evening. Locally rough seas may develop near and to the west of these winds. A tightening pressure gradient between a weakening cold front approaching the northwestern Caribbean and low pressure in the south-central basin will support fresh to strong trade winds and rough seas in the central Caribbean beginning on Wed and into the upcoming weekend. Winds may approach near gale- force offshore of Colombia late Wed. Elsewhere, a persistent east swell will continue to lead to rough seas over the Atlantic waters and passages of the Lesser Antilles into early Wed before seas slightly subside. New mixed north and east swell is expected to bring rough seas over these same waters starting late Wed night.

Atlantic Ocean

A weak cold front extends southwestward from a 1004 mb low north of the area near 33N61W to 31N64W to 26N71W and to 25N76W. Isolated showers and thunderstorms are east of the front to near 60W and north of 28N. A stronger cold front extends from near 31N69W to 27N75W to the central Bahamas and to the Straits of Florida. Fresh to strong southwest winds are ahead of both fronts while similar wind speeds from the northwest in direction are behind the stronger front. These winds are occurring roughly north of about 27N between 51W and the northeastern Florida/southern Georgia coast. Seas are 8 to 11 ft with these winds. Otherwise, a 1020 mb high center near 25N46W is dominating the Atlantic north of 23N between 35W and the Florida/southern Georgia coast, with gentle to moderate clockwise winds and seas of 6 to 9 ft in moderate to large northerly swells. For the tropical Atlantic from 07N to 23N between 35W and the Lesser Antilles, moderate to fresh, to at times, locally strong trade winds and seas of 6 to 9 ft seas are present. Gentle to moderate southerly winds and seas of 5 to 7 ft seas are present over the remainder of the Atlantic.

For the forecast, rough seas in west swell east of 68W will be reinforced by additional large northwest swell today through late tonight following in behind a stronger cold front that will quickly move eastward overtaking the aforementioned cold front tonight. This next front is followed today by fresh to strong northwest winds north of about 28N between 67W and 80W. By late this afternoon these winds are expected to be north of 29N between 60W and 66W before shifting northeast of the area late tonight as the front begins to stall. The northwest swell gradually subside Wed and Wed night as it shifts to the NE forecast waters. At that same time rough seas in long period east swell will begin to move into the southeast forecast waters and linger through the remainder of the forecast period. Looking ahead, fresh to locally strong southwest winds and rough seas may develop offshore northern Florida starting Wed as a low pressure system moves off the east coast of the U.S. Its associated cold front should move across the waters east of Florida from Wed night through the end of the weak as it weakens, and eventually stalling over the NE offshore zones Sat and dissipate Sat night. Fresh west to northwest winds will follow the front through late Thu.

Posted 3 hours ago by NHC Forecaster Aguirre