Tropical Waves

A tropical wave is along 30W from 12N southward, moving westward at 15-20 kt. No significant convection is observed near this tropical wave at this time.

A tropical wave is analyzed south of Barbados along 59W, moving westward at 10-15 kt. Scattered moderate convection is evident over Guyana and western Venezuela.

A tropical wave in the western Caribbean is near 82W, south of 14N and into the Eastern Pacific region to near 05N. The position is based in part on the morning upper air sounding from San Andres Island. This wave is drifting west at 5 kt. No significant convection is noted at this time.

Monsoon Trough/ITCZ

The monsoon trough enters the Atlantic near Dakar, Senegal and continues southwestward to 05N25W. The ITCZ extends from 03N30W. The ITCZ continues form 03N30W to 01N50W. No significant convection is evident at this time.

Gulf Of America

Numerous moderate to scattered strong convection is active over the central Gulf this afternoon, along a squall line reaching from just south of the mouth of the Mississippi River to 24N94W. Scattered moderate convection is also active near 28N87W, and off Brownsville, Texas. This convection is active in an area of upper level divergence, ahead of a mid/upper level trough reaching from central Texas to the Bay of Campeche. Strong gusty winds and rough seas are likely along the squall line. Gentle to moderate SE winds and 2-4 seas are noted elsewhere.

For the forecast, the Atlantic ridge extends across Florida into the Gulf region. This system will continue to support a gentle to moderate E to SE wind flow through the middle of the week, with the exception of fresh to strong winds pulsing off NW Yucatan from the late afternoons and into the night time hours due to local effects associated with a thermal trough. An upper-level disturbance continues to enhance the development of numerous showers and thunderstorms over the western Gulf, more concentrated over the NW part of the basin. These thunderstorms are capable of producing gusty winds, frequent lightning, limited visibility and locally rough seas. The SE flow will continue to advect abundant tropical moisture through at least the middle of the week helping to induce more convective activity across the Gulf waters. Mariners are urged to keep up with the latest forecast.

Caribbean Sea

The pressure gradient between the subtropical ridge and the Colombian Low continues to support fresh to strong trades in the central Caribbean, including off the southern tip of Hispaniola, and in the Gulf of Honduras, as noted in recent scatterometer satellite data. Elsewhere, trades are moderate to fresh per the latest scatterometer data. Seas are 4-7 ft across the basin.

For the forecast, the pattern will continue to support fresh to strong trades over the south-central Caribbean with rough seas through at least Wed night. Fresh to locally strong trades will pulse each evening over the Gulf of Honduras through the period. Fresh trades elsewhere across the basin will begin to increase in coverage starting Mon as a stronger Atlantic high pressure begins to shift southeastward tightening the pressure gradient.

Atlantic Ocean

A broad subtropical ridge dominates the Atlantic waters, providing moderate to fresh trades and 4-7 ft seas across the basin mainly south of 25N. Winds are light to gentle north of 25N, with 3-5 ft seas, in closer proximity to high pressures centered north of the area.

For the forecast west of 55W, winds are forecast to increase over most of the waters S of 25N starting Mon, including the waters between Cuba and the Bahamas as well as the entrance to the Windward Passage as a stronger Atlantic high pressure begins to shift southeastward tightening the pressure gradient. The high pressure will then begin to weaken Wed allowing for the tight pressure gradient to slacken leading to diminishing winds and seas. Fresh to strong trades will pulse north of Hispaniola through Tue night into Wed morning creating moderate to rough seas. The western part of a cold front will push south across the eastern portion of the area from tonight into early Mon before stalling near 27N, and dissipating on Tue. Fresh to strong northeast winds along with moderate to rough seas will follow the front, with these marine conditions subsiding on Tue.

Posted 4 hours ago by NHC Forecaster Christensen