Based on 1200 UTC surface analysis and satellite imagery through 1620 UTC.

Special Features

West Atlantic Gale Warning: The National Weather Service in Miami, FL has issued a GALE WARNING for coastal waters off of SE Florida. 20 to 30 kt winds with gusts to 35 kt and 6-9 ft seas are expected from 2200 UTC tonight through 1500 UTC Sunday. For more information, please see local products at www.weather.gov/mfl and the latest High Seas Forecast issued by the National Hurricane Center at website: https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml

Monsoon Trough/ITCZ

The monsoon trough extends from 15N17W to 05N20W. The ITCZ extends from 05N20W to 01N50W. Scattered moderate convection is along and north of the ITCZ to 07N. Scattered moderate isolated strong convection is south of the ITCZ to 04S.

Gulf Of Mexico

A strong pressure gradient between 1035 mb high pressure over New England and lower pressure over the Great Plains and Mexico provides for fresh to strong SE winds across the Gulf of Mexico. In response to these prevailing winds, seas have built to 8-10 ft in the Gulf waters north of 20N west of 91W where fetch is maximized. Fetch is defined as the distance over which winds from generally constant speed and direction build seas. Elsewhere, seas are 4-7 ft.

For the forecast, fresh to strong southeast winds will continue over much of the Gulf through Sun night. Seas are expected to peak near 10 ft in the NW and central Gulf today and Sun. Winds will pulse to fresh to strong speeds near the Yucatan Peninsula each evening through the forecast period.

Caribbean Sea

A surface trough extending west to east across Hispaniola and an upper level trough over the western Atlantic are producing scattered showers and tstorms across the eastern Greater Antilles and surrounding waters. Heavy rains and flooding have been occurring in Hispaniola during the last week, and it is possible that continued rains may result in localized flash flooding, especially in hilly terrain and low-lying areas. Please refer to bulletins from your local weather service agency for more details.

Strong NE winds were detected by satellite scatterometer this morning within the Windward Passage and off the coast of SE Cuba. Elsewhere in the NW Caribbean, fresh trades prevail. Seas are 5-7 ft in these areas of fresh to strong winds. Elsewhere in the basin, scatterometer indicates gentle to moderate trades. Seas are 3-5 ft.

For the forecast, strong high pressure centered off the New England coast will support fresh to occasionally strong winds in the Gulf of Honduras, the lee of Cuba, the Windward Passage, and south of Hispaniola through early next week. Seas will peak near 9 ft during the period of strongest winds. Moderate to locally fresh easterly winds will prevail in the rest of the basin. Northerly swell will bring seas of 8 ft through the passages in the NE Caribbean early next week.

Atlantic Ocean

A surface trough extends from 30N57W to 24N64W. Scattered showers are along the trough. North and west of the trough, NE winds are moderate to fresh, including across the Bahamas, Florida Straits, and approaches to the Windward Passage. Within the Windward Passage, winds are at strong speeds. These winds across the W Atlantic waters provide for 5-7 ft seas north of 20N and west of 55W. 1014 mb low pressure is near 18N42W.The remainder of the tropical Atlantic is experiencing gentle to moderate trades and 4-7 ft seas.

For the forecast west of 55W, a cold front will move through the eastern forecast waters this weekend before stalling and weakening over the far southeastern waters late Sun through Mon night. Northerly swell behind the front will build seas to a peak of 12 ft over the NE waters by Sun. Fresh to strong north to northeast winds will prevail N of 28N behind the front tonight through Sun. Moderate to fresh winds will prevail elsewhere into early next week. More tranquil marine conditions are expected by midweek as high pressure becomes centered over the NW waters.

Posted 48 minutes ago by NHC Forecaster Mahoney