Tropical Waves

A tropical wave has emerged off the west coast of Africa. Its axis extends is long 17W, south of 11N. Scattered showers and isolated thunderstorms are near the northern end of the wave axis.

A new tropical wave was added to the 0600 UTC surface map along 23W, south of 11N based on satellite imagery and wave diagnostic. Scattered moderate convection is near the wave axis.

A tropical wave is along 32W, south of 10N, moving westward at 15 to 20 kt. Scattered moderate convection is observed from 04N to 08N between 30W and 36W.

Another tropical wave is along 42W, south of 11N, moving westward at around 15 kt. Scattered moderate convection is where the wave meets the ITCZ, from 03N to 06N between 40W and 47W.

A tropical wave is in the central Caribbean Sea near 78W, south of 19N, moving westward at around 15 kt. The wave is interacting with an upper-level low centered south of Jamaica. This system is helping to induce scattered moderate convection over the majority of the central Caribbean, including western Venezuela and northern Colombia.

Monsoon Trough Itcz

The monsoon trough remains over Africa. The ITCZ extends from the coast of Sierra Leone near 07N12W to 05N30W to the coast of Brazil near 03N51W. Most of the convective activity across the area is associated with the above mentioned tropical waves.

Gulf Of America

The Atlantic high pressure extends westward across Florida into the Gulf region supporting gentle to moderate E to SE winds east of 90W, with seas 1 to 3 ft, while moderate to locally fresh SE winds and seas 3 to 5 ft prevail west of 90W. Scattered showers and thunderstorms are noted along the coast of Mexico and adjacent waters as well as over the western Bay of Campeche.

For the forecast, a ridge will continue to dominate the Gulf region through Fri supporting gentle to moderate east to southeast winds over the eastern Gulf, and moderate to locally fresh winds in the western Gulf. Slight to moderate seas will prevail. The exception will be off the Yucatan Peninsula, where a diurnal trough will support moderate winds to pulse to fresh, occasionally strong, during the evenings through at least Wed. Looking ahead, a trough, or low pressure, may emerge from the Yucatan Peninsula into the Bay of Campeche, perhaps from late Thu through Fri night accompanied by numerous showers and thunderstorms along with fresh to strong winds and building seas.

Caribbean Sea

A tropical wave is over the central Caribbean. Please see the Tropical Waves section above for more details, including any associated significant convection.

Otherwise, high pressure north of the area centered SW of the Azores extends a ridge to the SE Bahamas. This pattern supports moderate to locally fresh E to SE trade winds and moderate seas to 6 ft across the majority of the basin. An upper-level low located south of Jamaica is helping to induce scattered showers and thunderstorms over most of the central Caribbean. Elsewhere, patches of low level clouds, embedded in the trade wind flow, are noted producing isolated to scattered passing showers.

For the forecast, as the pressure gradient tightens further between the Atlantic ridge and a broad area of low pressure located over the eastern Pacific offshore of Central America, expect an increase of the trade winds to fresh to strong speeds, with moderate to rough seas starting this evening in the north-central and NW Caribbean and lasting through the rest of the period. In addition, a trough, or low pressure, may emerge from the Yucatan Peninsula into the Bay of Campeche perhaps from late Thu through Fri night keeping a tight pressure gradient over the NW Caribbean, including the Gulf of Honduras. Elsewhere, moderate to fresh winds and mostly moderate seas will prevail.

Atlantic Ocean

Four tropical waves are moving westward between the western coast of Africa and the Lesser Antilles. Please refer to the Tropical Waves section for details, including any related significant convection.

A surface trough extends from 28N72W to the central Bahamas into eastern Cuba. Scattered showers and isolated thunderstorms are near the trough axis. The remainder of the Atlantic forecast area is dominated by a broad subtropical ridge, anchored by a 1033 mb high pressure situated SW of the Azores near 36N31W. Under the influence of this system, a gentle to moderate E to SE flow with moderate seas is seen N of 20N E of the trough to about 40W. Fresh to locally strong NE to E winds and moderate to rough seas are found north of 16N and east of 40W, including the Canary Islands. Moderate to fresh trades and moderate seas are elsewhere S of 20N between the coast of Africa and the Lesser Antilles.

For the forecast west of 55W, the aforementioned trough will remain nearly stationary through the early part of the week. A weak cold front will move across the N waters Tue, then stall near 27N through Wed, gradually dissipating by Thu. High pressure in the wake of the front will shift eastward north of the area through the end of the week while weakening, with the associated ridge extending toward Florida and southeastern Georgia. The related pressure gradient will generally allow for gentle to moderate winds and slight to moderate seas. Increasing moisture resulting in unsettled weather conditions is likely to impact the far western section of the basin during the week.

Posted about 5 hours ago by NHC Forecaster GR