Special Features

Caribbean Gale Warning: The pressure gradient between the Bermuda High and the Colombian low will continue to support fresh to strong trades in the south-central and portions of the SW Caribbean through Mon night. Over the weekend, the ridge N of the region will shift southward, acting to increase the pressure gradient and accelerating the winds offshore Colombia and in the Gulf of Venezuela to near gale-force speed and to gale-force speed at night. Rough seas will prevail there, building to very rough at times this weekend with the increase in wind speed.

Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website - https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details.

Tropical Waves

A tropical wave is along 19W south 20N. Scattered to numerous moderate convection is noted from 09N to 13N between 20W and 25W.

A second tropical wave is along 39W S of 20N, and moving west at 15 to 20 kt. Scattered moderate convection is from 08N to 11N between 34W and 40W.

A third tropical wave is along 52W S of 20N, moving west at 15 to 20 kt. No significant convection is associated with this wave at this time.

Monsoon Trough/ITCZ

The monsoon trough enters the Atlantic through the coast of Senegal near Dakar and continues southwestward to near 11N35W. The ITCZ extends from 10N40W to the coast of Venezuela near 09.5N61W. Aside from the convection associated with the tropical waves, limited convective activity is noted elsewhere.

Gulf Of America

Weak ridging extends from the western Atlantic to the west-central Gulf. This pattern is supporting gentle to moderate E to SE winds across the Gulf. Seas are 2-4 ft over the southwest Gulf and 1-3 ft elsewhere. Numerous showers and thunderstorms are moving off the Florida coast north of Tampa Bay into the far northeast Gulf. Scattered showers and thunderstorms are active elsewhere north of the Yucatan Channel, and off the coast of Veracruz.

For the forecast, the surface ridging will dominate across most of the Gulf through late Tue, supporting gentle to moderate E to SE winds north of 24N along with slight seas. Pulses of fresh winds will occur north and west of the Yucatan Peninsula and into the Bay of Campeche each night as a surface trough migrates from the Yucatan Peninsula to the SW Gulf, locally strong tonight. Slight to moderate seas are forecast for this portion of the basin through Tue night.

Caribbean Sea

The pressure gradient between a 1027 mb high located near Bermuda and the Colombian low continues to support fresh to strong trades over the south-central Caribbean, including the Gulf of Venezuela, along with moderate to rough seas. Moderate to locally fresh trades are elsewhere over the E Caribbean, the Gulf of Honduras and in the lee side of Cuba. Seas are generally moderate. Scattered showers and thunderstorms are active from Jamaica to Grand Cayman to the coast of Cuba.

For the forecast, the ridge north of the region will shift southward, acting to increase the pressure gradient and accelerating the winds offshore Colombia and in the Gulf of Venezuela to near gale- force speed and to gale-force speed at night. Rough seas will prevail there, building to very rough at times this weekend with the increase in wind speed. Fresh winds will pulse in the Gulf of Honduras and Windward Passage through the forecast period, except over the weekend when winds may pulse to strong speed. Otherwise, mainly moderate to fresh easterlies will prevail elsewhere.

Atlantic Ocean

Scattered showers and thunderstorms are active off the central Bahamas, and along a surface trough reaching from north of the central Bahamas southward toward eastern Cuba. Farther north, 1027 mb high pressure is centered near Bermuda. Recent scatterometer satellite passes confirmed fresh to strong E winds on the northern end of the trough from 25N to 28N between 70W and 75W. A concurrent altimeter satellite pass showed rough seas to 10 ft in this area as well. Moderate to fresh easterly winds and 5-7 ft seas prevail elsewhere west of of 65W. Farther east, fresh to strong NE winds and 5-7 ft seas are noted across the Canary Islands and off Western Sahara. Gentle to moderate easterly flow and 4-6 ft seas are noted over the remainder of the basin.

For the forecast west of 55W, the surface trough will induce additional shower and thunderstorm activity across the Florida seaboard and offshores Fri morning before shifting west of the area Fri night into early Sat. Aside from the shower activity, the surface trough will bring fresh to locally strong winds and rough seas across the Bahamas offshores through tonight. Fresh E winds will prevail N of Hispaniola and in the approaches of the Windward Passage through the period, reaching strong speeds Sun night, Mon night, and Tue night as the Bermuda High shifts southward.

Posted 26 minutes ago by NHC Forecaster Christensen