Special Features

Western Atlantic Gale Warning: Gale-force northwest to north winds and rough seas of 10 to 15 ft (3 to 4. 5 M) in north swell are expected over some portions of the waters east of northern Florida this evening and into Mon morning in the wake of an arctic cold front that has recently moved over the waters east of northeast Florida along a position from near 31N78W to inland northern Florida near Saint Augustine. Widespread strong to near- gale force northerly winds along with rough seas in northwest to north swell are expected north and northeast of the Bahamas northward and west of a line from 31N50W to 22N72W through early on Tue. The swell will reach the islands of the northeast Caribbean late Tue night into early Wed as it merged with east swell. Seas will begin to gradually subside from NW to SE Wed through Wed night. 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 information.

East Atlantic Significant Swell Event: Large, long period north to northeast swell continues to affect most of the eastern tropical and subtropical Atlantic. Seas 12 ft or greater are currently from 10N to 19N between 26W and 45W, and from 10N to 30N east of 26W along with peak seas to 13 ft (4 M)just southwest of the Canary Islands. The swell direction is from the N to NE winds at a period of 10-16 seconds. With persistent fresh to strong northeast northeast trade winds, the area of 12 ft (4 M) or greater seas will expand westward to near 50W by early Mon before they slowly subside from NE to SW going into Tue. For information east of 35W please read the latest High Seas Forecast issued by Meteo-France at website: https: //wwmiws. wmo. int/index. php/metareas/affiche/2. For information west of 35W, please read the latest High Seas Forecast issued by the National Hurricane Center at website: https: //www. nhc. noaa. gov/text/MIAHSFAT2. shtml.

Monsoon Trough Itcz

The monsoon trough axis enters the Atlantic near 08N13W, and continues southwestward to 05N19W, where it transitions to the ITCZ to 04N30W to 02N40W and to inland South America near 01N52W. Numerous moderate to isolated strong convection is seen within 120 nm south of the trough and ITCZ between 16W-22W. Scattered moderate convection is within 120 nm south of the trough between the coast of Africa and 16W and within 30 to 60 nm of the ITCZ between 22W-27W.

GULF OF AMERICA,

An arctic cold front extends from near Apalachicola to the northeast Mexico-Texas border as strong high pressure builds in over the basin behind it. The very tight pressure gradient between the front and the high pressure is bringing strong to near-gale force northeast winds, with frequent gusts to gale force over Gulf coastal waters and occasional gusts to gale-force just east of these waters as indicated in the latest buoy observations and by a 1620Z Ascat pass. Seas with these winds are in the range 8 to 11 ft (2. 5 to 3. 5 M). Scattered showers and thunderstorms moving southward are present south of the front to near 22N and west of 96W to just inland the coast of Mexico. The latest Ascat satellite data shows gentle to moderate north to northeast winds elsewhere across the basin along with seas of 4 to 6 ft. Lower seas of 3 to 4 ft are over the extreme eastern Bay of Campeche.

For the forecast, the cold front will sweep across the rest of the Gulf reaching south of the basin Mon night. Winds will become fresh to strong in speeds and northeast in direction across just about the entire Gulf on Mon, except for mostly strong northerly winds along the coast of Mexico near Tampico and Veracruz. By late Mon night, gentle to moderate east winds are expected north of 26N, and mostly fresh northeast to east winds are expected south of 26N. Seas at that time are expected to be 5 to 7 ft, except for higher seas of 6 to 9 f t in north to northeast swell south of 26N. Afterward, seas will slowly subside during the middle portion of the week as high pressure dominates the region.

CARIBBEAN SEA,

Atlantic high pressure has shifted eastward to the central Atlantic. As as result, the trade winds over the eastern Caribbean have diminished to moderate to fresh speeds, but continue at fresh to strong speeds across the central Caribbean waters. Gentle to moderate trade winds are over the western Caribbean. Latest satellite altimeter data passes indicate seas of 5 to 8 ft over most of the basin east of about 81W, with the exception of higher seas of 7 to 9 ft from 11N to 16N between 72W and 80W. Lower seas of 4 to 5 ft are west of 81W. Seas may be locally higher in Atlantic Passages of the Lesser Antilles due to arriving east swell. Otherwise, a trough is analyzed over the northwestern Caribbean along a position from near 20N84W to 18N86W and to near 16N 87W. An area of scattered to numerous moderate convection is east of the trough from 16N to 18N between 84W and 86W as an upper-level impulse rides along a subtropical jet stream present over the western Caribbean. Isolated showers and thunderstorms are elsewhere south of 19N between 80W and 88W. Mostly overcast low and mid- level clouds are present north of 16N between 78W and 84W. Patches of light to moderate rain along with isolated showers are embedded within this area of cloudiness.

For the forecast, fresh to occasionally strong trade winds and moderate to rough seas over the central Caribbean will continue to diminish as Atlantic high pressure shifts well to the northeast of the region. Elsewhere, fresh to locally strong trade winds and rough seas in large east swell will prevail over the tropical Atlantic waters, through the Atlantic passages and into the eastern part of the basin through Mon night. A cold front will enter the northwestern Caribbean on Mon, followed by increasing winds and building seas behind the front. This front is expected to reach from central Cuba to northern Belize Tue morning, then will stall and gradually dissipate through Wed. High pressure will build over the western Atlantic Wed night through Thu night to bring a return to fresh to strong trades across the central Caribbean.

ATLANTIC OCEAN,

Please see the Special Features section for more information on a gale warning for the western Atlantic waters offshore northern Florida, and for a significant swell event in the eastern Atlantic.

An arctic cold front is just inland the Georgia coast. A trough is analyzed from near 31N73W southwestward to central Bahamas and to the coast of Cuba near 22N78W while at the same time a rather broad upper-level trough is advancing eastward over the eastern United States. Gentle to moderate southeast to south winds are between the trough and 63W while light and variable winds are west of the trough, except for gentle to moderate northwest winds from 27N to 29N and moderate to fresh northwest winds north of 29N. Seas are 4 to 6 ft west of the trough, except for lower seas of 3 to 4 ft south of about 25N. A well pronounced jet stream branch rounds the base of the trough from near 31N79W to the eastern Gulf of America near 26N87W. Abundant overcast multilayer cloudiness is evident between 67W and 79W, and mostly mid to upper broken to overcast clouds shifting eastward are north of 21N between 55W and 67W. Satellite imagery also shows scattered to numerous showers and thunderstorms north of 21N between 67W and 73W. Isolated showers and thunderstorms moving northeast around 10 kt are north of 27N between 73W and 78W. Isolated showers are south of 27N between 73W and 79W.

A 1028 mb high center is analyzed at 31N43W as a dissipating stationary extends from 31N41W to 31N55W. Isolated showers are possible north of 30N between 35W and 40W. A tight pressure gradient between the high pressure and relatively lower pressure to its south is sustaining fresh to strong trade winds over the waters south of about 25N and east of 62W. Seas are 8 to 11 ft with these trade winds, except as noted above in the Special Features section.

For the forecast W of 55W, the above mentioned arctic cold front will move to over the far northwest waters east of northern Florida early this evening, followed by strong to near gale- force northerly winds and rapidly building seas through Mon morning. Gale-force winds are expected behind the front this evening through early Mon. The front will reach from just east of Bermuda to the NW Bahamas and to the Straits of Florida by Mon morning, then stall from near 29N55W to the southeastern Bahamas and central Cuba by Tue morning. Large north swell will build across the regional waters behind the front tonight through Tue before subsiding.

Posted about 3 hours ago by NHC Forecaster Aguirre