Special Feature

Heavy rainfall across the Yucatan peninsula and northern Belize: Broad low pressure is expected to develop over northern Central America and southern Mexico over the next couple of days. The combination of sustained upper-level divergence east of an upper low that is located over the eastern Bay of Campeche, and a tropical wave moving through the Yucatan Peninsula while abundant deep tropical moisture remains in place will provide the potential for heavy rainfall over Belize and the Yucatan Peninsula into Sat. Increasing deep convection is presently over the eastern Bay of Campeche and portions of the Yucatan Peninsula. The heaviest rainfall accumulations may be as high as 6 to 8 inches over this 48 hour period, primarily across northern Belize and southern part of the Mexican state of Quintana Roo. Rainfall of up to 2 to 4 inches is possible across eastern Campeche and eastern Yucatan states as well. Localized flooding is possible. Please refer to local meteorological agencies for further guidance.

Tropical Waves

A far eastern tropical wave has its axis near 26W-27W, S of 16N, moving westward 10 to 15 kt. Nearby convection is discussed in the Monsoon trough/ITCZ section below.

A central Atlantic tropical wave has been added to the 06Z analysis along 46W, S of 15N, moving westward near 15 kt. The wave axis is clearly identified in precipitable water imagery. Nearby convection is discussed in the Monsoon trough/ITCZ section below.

A central Atlantic tropical wave has its axis near 56W-57W, S of 12N, moving westward at 15 to 20 kt. Nearby convection is discussed in the Monsoon trough/ITCZ section below.

The axis of an eastern Caribbean tropical wave is near 68W, S of 17N, moving westward at 15 to 20 kt. Scattered showers prevail between the wave axis and 61W, to the south of 15N.

Another eastern Caribbean tropical wave has its axis near 73W-74W, south of 18N, moving westward at about 15 kt. No significant convection is occurring at the present time near this wave.

Monsoon Trough Itcz

The monsoon trough axis extends off the coast of Africa near 14N17W and extends southwestward to 08N25W, where it transitions to the ITCZ, continuing on to the coast of Brazil near 05. 5N53W. Scattered to numerous moderate to strong convection is across the waters of W Africa from 02N to 12N E of 18W. Scattered moderate isolated strong convection is noted from 04. 5N to 11. 5N between 19W and 32W, from 05N to 07. 5N between 36W and 41W, and from 05. 5N to 07N between 51W and 54W.

Gulf Of America

A surface trough extends from the eastern Bay of Campeche northeastward to the offshore waters of the Yucatan Peninsula, and extends into the middle atmosphere. Recent satellite scatterometer data showed fresh to strong E to SE winds across the northern coast of the Yucatan Peninsula to 24N, and east of the surface trough. This feature is producing scattered showers and isolated thunderstorms across the basin S of 25N between the Yucatan Channel and 93. 5W. Weak high pressure across the western Atlantic extends a ridge westward across Florida and into the NE Gulf, and is producing a modest pressure gradient between the ridge and the trough. Seas are estimated to be 5-7 ft across this area. Elsewhere across the basin, moderate SE winds prevail across the western Gulf, with 3-5 ft seas, with gentle southerly winds over the eastern Gulf and 2-3 ft seas.

For the forecast, high pressure will persist across northeastern Gulf through Tue. Farther south, a broad trough of low pressure extending from the Yucatan Peninsula northeastward into the southern Gulf will shift slowly northwestward through the weekend, and move inland across NE Mexico and S Texas on Sun. This pattern will support fresh to strong SE winds and moderate to rough seas shifting from the northwestern Yucatan Peninsula to the coast of Texas through early Sun, accompanied by numerous showers and thunderstorms. Winds and seas will diminish Mon and Tue after the low pressure moves inland and weakens.

Caribbean Sea

1019 mb high pressure near 29N69W extends a ridge westward across Florida and the NE Gulf of America. Two tropical waves are moving quickly across the central Caribbean overnight, south of the ridge. Recent satellite scatterometer data showed fresh to strong SE winds across the far northwest Caribbean west of 80W, with near- gale force wind between Roatan and northern Belize. These winds are occurring between the Atlantic ridge to the northeast, and a surface trough over northern Central America. Seas are likely 5-8 ft in this area. Scattered showers and isolated thunderstorms are occurring across the northwest Caribbean W of 81W. This pattern is also supporting fresh trade winds across the south- central and southeast Caribbean, with strong winds pulsing off northeast Colombia and northwest Venezuela, where seas are 7-9 ft. Moderate E winds prevail elsewhere with 4-6 ft seas. For the forecast, the Atlantic ridge will generally remain in place north of region through early next week to support a large area of fresh to strong trade winds and moderate to rough seas across the central Caribbean through Sun, as a pair of tropical waves move westward across the region. Expect highest winds and seas off the coast of Colombia. Fresh to strong SE winds and rough seas will also persist over the northwestern Caribbean, to the W of 83W, including the Gulf of Honduras, through Sat evening. Expect active showers and thunderstorms across portions of the Yucatan Channel and adjacent Yucatan waters through early Sat.

Atlantic Ocean

Scattered showers and isolated thunderstorms remain active N of 26N between 50W and 59W, associated with a weak area of low pressure near 29. 5N58. 5W, with an lingering frontal trough extending eastward to 31N41W. A broad ridge extends from the Azores to south of the trough near 24N55W. 1019 mb high pressure is centered W of the low pressure near 29N69W and extends a weak ridge westward across Florida into the eastern Gulf. This pattern is support moderate to fresh NE to E trade winds and 5-7 ft seas south of 22N and between 35W and 60W, and moderate E to SE winds @ of 22N between 60W and 80W. Mostly gentle breezes and 4-6 ft seas prevail elsewhere within the ridge.

For the forecast west of 55W, the current western Atlantic ridge will generally remain in place through early next week. The weak low pressure near 29. 5N58. 5W will shift NE and out of the forecast waters through early Sat, then allow the ridge to reorganize across the area through early next week. This pattern will support moderate E-SE trade winds S of 22N and gentle anticyclonic winds elsewhere through Sun. Fresh SW winds will develop across the NW waters N of 29N and W of 74W Sun evening through Tue, as a weak frontal system moves through the SE U. S. Expect fresh to strong winds each afternoon through late evening across waters near Puerto Rico and Hispaniola.

Posted about 5 hours ago by NHC Forecaster Stripling