Special Features

Western Atlantic Gale Warning: A stationary front extends from 31N72W SW to a 1010 mb low near 29N74W then transitions to a cold front that moves across SE Florida near 25N80W. The low pressure will track slowly NE, lifting N of the area near Bermuda Thu, while the front drifts E, extending SW from near Bermuda to western Cuba later Thu into Fri. Thunderstorms with gusty winds will impact waters along and east of the track of the low pressure. The pressure gradient between strong high pressure to the north of our waters and the front is supporting NE gales offshore NE Florida. These gales will spread eastward to about 72W, mainly north of 28N, through Wed night, before gradually ending as the low pressure moves north of the area. Very rough seas of 15 to 20 ft will be generated by these gales, and rough seas in N swell will impact a much larger area through the end of the week. The front is likely to linger over the basin into the weekend, so marine conditions could be slow to improve.

East Atlantic Large Swell: Long period NW to N swell behind a cold front that extends across NW Africa and the eastern Atlantic is creating seas of 11 to 13 ft north of 21N and east of 40W. This swell event will continue to propagate southward with seas 8 ft or greater reaching as far south as 10N on Wed. By late Thursday afternoon or early in the evening, the swell should decay enough to allow seas to drop below 12 ft.

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.

Gale Warning E of 35W: Meteo-France has issued a Gale Warning for the forecast zone of Madeira. The forecast calls for NW gales to 40 kt, with severe gusts from 08/12 UTC to 09/00 UTC at least. Very rough seas in NW swell are also reaching the islands.

For more details, refer to the Meteo- France High Seas Forecast listed on their website https://wwmiws.wmo.int

Monsoon Trough/ITCZ

The monsoon trough enters the Atlantic through the coast of Liberia, Africa and continues SW to 02N21W. The ITCZ extends west-southwestward from 02N21W to 00N35W to NE Brazil near 00N48W. Scattered moderate to isolated strong convection is from 03S to 07N between 05W and 38W.

Gulf Of America

The tail of a front stalls across southern Florida, entering the Gulf SE waters near 25N81W and continuing to a 1010 mb low near 24N85W from where a cold front stretches SW the NE Yucatan Peninsula offshore waters near 22N88W. Surface ridging has started to build across the northern Gulf, and is supporting fresh to near gale force NE winds across the NE Gulf offshores as confirmed by recent scatterometer data. Seas with these winds are rough to 10 to 11 ft. Elsewhere, winds are moderate or weaker, and seas moderate in the 4 to 7 ft range.

For the forecast, the front will stall over the far SE basin through Thu, and strong to near gale-force NE winds and rough seas will continue in the NE Gulf during this time. Conditions will gradually improve Fri into the weekend as the high pressure builds southwestward across the northern basin.

Caribbean Sea

The Atlantic ridge extends SW reaching the NE Caribbean. This system is supporting fresh to locally strong E to SE winds and seas of 5 to 7 ft across the eastern part of the basin. Gentle to moderate NE to E winds and 3 to 5 ft seas are ongoing across the SW Caribbean while light and variable winds and slight seas dominate the NW Caribbean. Scattered showers with embedded thunderstorms are seen over Hispaniola and E Cuba adjacent waters as well as in the Windward Passage.

For the forecast, fresh to strong trades will prevail over the central and eastern basin into Thu, with gentle to moderate winds to the west. Strong high pressure will then build southward from the western Atlantic, with a tightening pressure gradient leading to increasing winds, especially in the south-central basin.

Atlantic Ocean

A Gale Warning is in effect for the western Atlantic. Please refer to the Special Features section for more details.

A stationary front extends from 31N72W SW to a 1010 mb low near 29N74W then transitions to a cold front that moves across SE Florida near 25N80W. Recent scatterometer data confirm the presence of gales west of the low and front, over the NE and central Florida offshore waters. Seas with these winds are rough to very rough with peak seas of 16 ft N of the Bahamas. Aside from the winds and seas, heavy showers and tstms continue to affect the offshore waters N of 20N between 62W and 77W. Over the far E Atlantic, the tail of a cold front starts to weaken near 25N20W to 23N41W. Strong high pressure of 1038 mb SW of the Azores is driving a long-period N to NW swell that is affecting the central, eastern and tropical Atlantic waters. See the Special Features Swell section for further details. Otherwise, a broad surface ridge prevails elsewhere, supporting moderate to fresh E to SE winds and moderate to rough seas.

For the forecast west of 55W, please refer to the Special Features Western Atlantic Gale Warning section for all the information related to the above mentioned frontal boundary.

Posted 44 minutes ago by NHC Forecaster Ramos