Monsoon Trough/ITCZ

The monsoon trough axis remains inland Africa. The ITCZ passes through the coastal plains of Liberia near 07N11W to 05N25W to 03N36W and to 03N45W. Scattered moderate to isolated strong convection is within 120 nm north of the ITCZ between 30W and 45W.

Gulf Of Mexico

A cold front extends from the Florida Big Bend region southwestward to 26N89W and to inland Mexico just north of Tampico. A pre- frontal trough extends from NE Florida southwestward to Cross City, Florida and to the central Bay of Campeche near 19N94W. An overnight ASCAT satellite data pass reveals fresh to strong N winds over the far western Gulf north of 23N and west of 95W. Seas with these winds are 6 to 9 ft. Mostly fresh NE winds are elsewhere northwest of the front along with seas of 4 to 6 ft. The overnight ASCAT satellite data passes and buoy data observations have light to gentle winds south of the front. Seas there are generally 3 to 4 ft, except for higher seas of 5 to 7 ft in the SW Gulf.

For the forecast, the aforementioned cold front will shift across the remainder of the Gulf waters before moving SE of the basin this weekend. Fresh to strong northerly winds and building seas will follow this front. Winds to near gale-force, or with brief gusts to gale force may occur W of the front over the western portion of the central Gulf today and in the SW Gulf tonight. High pressure building in the wake of the front will shift E through Sun night as a trough develops in the far western Gulf. The resulting pressure gradient will support fresh to strong easterly winds and building seas over the waters W of 90W into early next week.

Caribbean Sea

Low pressure of 1008 mb is near 12N81W. This feature is on the eastern tip of the East Pacific monsoon trough that extends from the low southwestward to across the border of Costa Rica and Panama, continuing well into the eastern Pacific. A trough extends from the 1008 mb low north-northeastward to just southwest of Jamaica. Overnight ASCAT satellite data passes show light to gentle winds south of 17N between 74W and 83W. Moderate to fresh NE winds are north of 15N and west of 80W. Moderate to fresh easterly winds are over the rest of the sea. Moderate seas are over most of the basin.

Satellite imagery continues to exhibit increasing scattered to numerous showers and thunderstorms over the central portion of the sea south of 16N to near the coast of Colombia and between 72W and 75W. This activity is just west of a trough that extends from 17N71W to 11N75W. Similar activity is within an area that covers the waters from 15N to 19N between 75W and 81W, including the western part of Jamaica. A shortwave trough embedded in the upper-level southwesterly flow is helping to sustain this activity. Scattered showers and isolated thunderstorms are seen over the eastern Caribbean from 13N to 15N between 61W and 63W.

For the forecast, moderate to fresh trades are expected over most of the basin through Sat night. A cold front will move into the NW Caribbean this weekend, with winds strengthening over these waters in the wake of the front toward the end of the weekend. Fresh to strong winds will be over the majority of the basin going into the middle of next week.

Atlantic Ocean

A weakening trough that was previously a cold front is analyzed from 31N22W to 25N32W and to near 21N50W. Light to gentle winds are near the trough. Areas of light to moderate rain moving eastward are east of the trough from 23N to 31N. Long-period swell is sending seas of 8 to 9 ft near this trough. Meanwhile, a cold front is just offshore the NE Florida coast. Moderate to fresh northwest to north winds are behind the front along with seas of 4 to 6 ft. Rough seas are present north of 05N and east of 60W. Generally, moderate seas are over the remainder of the basin. To the east of the front, a 1022 mb high center is analyzed at 30N50W. Its associated anticyclonic wind flow consisting of moderate to fresh winds is south of 26N and between 42W and 65W. Light to gentle winds associated to the anticyclonic flow are north of 26N between 45W and 55W, and also north of 17N east 35W.

A trough extends from near 25N70W to the northwest coast of Haiti. Scattered moderate convection moving eastward is noted south of 23N and between 65W and 69W. Areas of moderate rain with embedded scattered showers are moving eastward from 22N to 26N between 60W and 69W. This activity is being driven by a rather pronounced jet stream branch that runs NE to SW from 28N63W to 23N78W.

For the forecast W of 55W, high pressure prevails over the forecast waters. The cold front that is just offshore the NE Florida coast will move across the NW part of the area today. The front is forecast to move across the waters through the weekend before becoming stationary from near 31N58W to 26N65W and to near the Windward Passage by Sun night. Moderate to fresh winds and moderate seas will follow the front. A coastal trough is expected to develop along the NE Florida coast Sat night and into Sun. A reinforcing cold front may move off the Florida coast early on Sun evening, and merge with the stationary front early next week.

Posted 30 minutes ago by NHC Forecaster Aguirre