Special Features

Caribbean Sea Gale Warning: The pressure gradient between central Atlantic high pressure and lower pressures over northern South America will continue to result in fresh to near gale trades over the central Caribbean for the next several days. Peak winds should pulse to gale-force just north of Colombia tonight before diminishing to just below gale-force Wed. These winds will again pulse back up gale-force at night over these same waters through the rest of period, except on Thu and Sun. Gale-force winds are also expected in the Gulf of Venezuela Fri night and Sat night.

Please refer to the latest NWS High Seas Forecast at website: https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details.

Tropical Waves

An eastern Atlantic tropical wave is along 28W, south of 14N, moving westward at 15-20 kt. Scattered moderate to isolated strong convection is observed from 05N to 12N and between 20W and 35W.

A central Atlantic tropical wave is along 50W, south of 17N, moving westward at 15-20 kt. Scattered moderate convection is present from 08N to 13N and between 47W and 55W.

An eastern Caribbean tropical wave is along 63W, south of 18N, moving westward at 15 kt. No significant convection is noted near the trough axis.

A western Caribbean Sea tropical wave along 83W, south of 20N, moving westward at 5-10 kt. A few showers and isolated thunderstorms are seen near the trough axis and nearby Nicaragua and Honduras.

Monsoon Trough/ITCZ

The monsoon trough enters the Atlantic through the coast of Mauritania near 18N16W and continues southwestward to 09N27W. The ITCZ extends from 09N29W to 08N49W, then continues from 08N51W to 08N59W. Scattered moderate to isolated strong convection is evident from 05N to 09N and east of 18W. Similar convection is found from 06N to 10N and between 35W and 43W.

Gulf Of America

An upper level low over the NW Gulf is enhancing showers and isolated thunderstorms over much of the basin south of 26N, with the strongest convection occurring in the Bay of Campeche. A 1020 mb high pressure over the eastern Gulf results in moderate to fresh easterly winds and moderate seas in the Bay of Campeche. Elsewhere, moderate or lighter winds and slight seas prevail.

For the forecast, relatively weak high pressure extending westward across the basin from the Atlantic will change little through Thu night, then shift northward to near the northern Gulf coast Fri through Sat night. The related pressure gradient will generally maintain gentle to moderate east to southeast winds across the Gulf south of about 26N, and light to gentle southeast to south winds north of about 26N, except for fresh to strong northeast to east winds offshore the Yucatan peninsula at night due to the diurnal trough that moves westward from the Yucatan peninsula. A mid to upper-level low acting on a very unstable and moisture-laden atmosphere will continue to result in scattered to numerous showers and thunderstorms over mostly the SW Gulf, with scattered showers and isolated thunderstorms elsewhere across the basin south of about 28N.

Caribbean Sea

Please refer to the Special Features section above for details on a Gale Warning.

Divergence aloft is supporting a few showers and isolated thunderstorms over the western Caribbean and the western Greater Antilles. A strong subtropical ridge over the central Atlantic continues to dominate the Caribbean. Outside of the Gale Warning area, strong to near gale-force easterly trade winds and rough seas are found across the central Caribbean Sea. Fresh to strong NE-E winds and seas of 5-8 ft are occurring in the Gulf of Honduras and the Windward Passage. Meanwhile, moderate to fresh easterly breezes and moderate seas are present in the eastern Caribbean. Elsewhere, moderate or lighter winds and slight to moderate seas are prevalent.

For the forecast, the pressure gradient between the Bermuda-Azores High north of the area along with lower pressure over N South America will produce fresh to near gale trades over the central Caribbean for the next several days. Peak winds should reach gales just north of Colombia tonight before slightly diminishing tomorrow. Additionally, trades over the Gulf of Honduras will pulse to fresh to strong late afternoons and evenings through the weekend. A vigorous tropical wave should reach the Lesser Antilles Wed evening, bringing fresh to strong trades over the E Caribbean on Thu and Fri.

Atlantic Ocean

An expansive subtropical ridge extends across the tropical Atlantic along 27N, anchored by a 1027 mb high pressure system near 27N43W. The pressure gradient between this ridge and lower pressures in the deep tropics results in strong easterly trade winds and rough seas south of 23N and between 70W and 75W. Fresh to locally strong easterly breezes and seas of 5-8 ft are found south of 24N and east of 45W. Moderate to fresh N-NE winds and seas of 4-7 ft are present north of the monsoon trough and ITCZ to a line from 30N20W to 24N45W and east of 45W. Elsewhere, moderate or weaker winds and seas of 3-6 ft prevail. A weak front north of our area and divergence aloft sustain scattered showers and isolated thunderstorms north of 27N and between 40W and 70W.

For the forecast west of 55W, high pressure ridging near 27N will change little through Thu, then shift slightly north afterward. The associated gradient will continue to support moderate to fresh trades south of 23N, and light to gentle winds north of 23N, except north of 29N where moderate to fresh south to southwest winds will exist. Strong winds along with moderate to rough seas are expected at night north of Hispaniola, including approaches to the Windward Passage through the weekend.

Posted 4 hours ago by NHC Forecaster Delgado