Monsoon Trough/ITCZ

The monsoon trough enters the Atlantic through the coast of Sierra Leone near 08.5N13W and continues westward to near 08N19W. The ITCZ extends from 08N19W to 10N40W to the coast of Guyana near 07N58W. Scattered moderate convection is seen from 04N to 11N between 20W and 52W.

Gulf Of America

As of 1500 UTC, a surface trough is analyzed over the central Gulf, and extends from 26N90W to the eastern Bay of Campeche. Scattered showers, with embedded thunderstorms are near the northern end of the trough axis. The remainder of the Gulf region is under the influence of a ridge, anchored by a 1026 mb high pressure located over the State of Georgia. Moderate to fresh NE to E winds with moderate seas dominate the SE Gulf while gentle to moderate winds and slight to moderate seas prevail elsewhere.

For the forecast, moderate to locally fresh E winds will slowly diminish in the eastern Gulf today in the wake of a stationary front over the Yucatan basin. Gentle to moderate winds and slight to moderate winds are then expected over the basin tonight through Sat. Looking ahead, a strong cold front is slated to enter the northwestern Gulf on Sun and will sweep over the basin into early next week, with fresh to strong winds and building seas expected in the wake of the front.

Caribbean Sea

A stationary front extends across eastern Cuba and the NW Caribbean generating scattered showers and thunderstorms. Low-topped trade wind showers are noted across the remainder of the basin. The pressure gradient between high pressure N of the area and the front supports fresh to strong NE winds N of the front, and fresh NE winds in the lee of Cuba. These winds are reaching the Cayman Islands. Elsewhere, gentle to moderate trade winds are noted based on recent scatterometer data. Seas are in general moderate, with the exception of slight seas over the eastern Caribbean.

For the forecast, fresh NE winds will occur in the lee of Cuba and through the Windward Passage into this afternoon as a stationary front prevails over Cuba. Moderate to locally fresh winds will then pulse in this region into early Thu before the front dissipates. Elsewhere, mainly moderate trade winds and moderate seas are expected over much of the Caribbean through Fri, with locally fresh winds possible in the south-central basin and offshore of southern Hispaniola. A long-period N to NW swell will lead to rough seas east of the Lesser Antilles by late Thu, with a reinforcing E swell supporting rough seas through the Atlantic passages this weekend. Looking ahead, moderate to fresh E winds will develop over the central and eastern basin this weekend.

Atlantic Ocean

A cold front enters the forecast area near 31N50W and continues SW to near 25N63W, where it transitions to a stationary front that continues to eastern Cuba. Moderate to fresh N to NE winds and rough seas to 10 ft are behind the front, with seas 8 ft or higher affecting the offshores N of 27N and E of 70W. Moderate to fresh SW winds are observed N of 28N and east of the front to about 43W. Scattered showers are likely associated with the frontal boundary, with some thunderstorm activity in the vicinity of the Turks and Caicos Islands. High pressure follows the front and dominates the western Atlantic. E of the front, a 1021 mb high pressure located near 26N35W dominates the remainder of the Atlantic forecast area. Under the influence of this system, mainly light to gentle winds prevail, increasing to moderate speeds across the tropical Atlantic where a surface trough is analyzed. The trough runs from 16N50W to 06N51W. Scattered moderate convection is noted where the trough meets the ITCZ. Farther E, a cold front crosses between the Madeira and the Canary Islands and extends along 30N to about 30N30W. Rough seas, in long period NW swell, are propagating across the eastern Atlantic. A pair of altimeter passes indicate seas of 8 to 10 ft roughly N of 16N between 25W and 35W.

For the forecast west of 55W, moderate to fresh N to NE winds will occur over the waters north of the above mentioned front through late tonight as high pressure builds over the western Atlantic. Winds will slowly diminish into Thu as the cold front moves eastward and the stationary front slowly dissipates. Rough seas in N to NW swell will expand southeastward to areas north of 23N and east of 75W through this evening, and north of 20N on Thu. Seas in excess of 12 ft will be possible north of 27N and east of 63W through Thu morning. Rough seas will be reinforced over the waters east of 65W by Fri as a strong storm system passes north of the forecast area. Looking ahead, the next cold front may approach the northwest waters late this weekend.

Posted 2 hours ago by NHC Forecaster Gr