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Atlantic Tropical Weather Discussion


000
AXNT20 KNHC 171108
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1215 UTC Tue Mar 17 2026

Tropical Weather Discussion for North America, Central America
Gulf of America, Caribbean Sea, northern sections of South
America, and Atlantic Ocean to the African coast from the
Equator to 31N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 0600 UTC surface analysis and satellite imagery through 
1000 UTC.

...SPECIAL FEATURES...

Gulf of America Residual Swell: 
Residual NW to N swell behind a strong cold front will keep 12 to
16 ft seas in the southwestern Gulf, south of 25N including the 
Bay of Campeche until early this afternoon. Afterward, swell 
should be low enough to allow seas to drop below 12 ft.

Please refer to the latest High Seas and Offshore Waters Forecasts
issued by the National Hurricane Center at websites 
https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and
https://www.nhc.noaa.gov/marine/offshores.php for more details.

East Atlantic Long-period N Swell:
Large, long-period N swell generated by a large fetch of gale to
storm-force winds in the northeast Atlantic will migrate southward
and cross 31N this afternoon. Expected seas to quickly rise to
between 12 and 16 ft from 27N to 31N between 35W and 45W this
afternoon. These very rough seas will shift farther southward
tonight to near 24N Wed morning, and then linger in the general
area through at least Fri.

Please refer to the latest High Seas Forecast issued by the 
National Hurricane Center at website 
https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details.

...MONSOON TROUGH/ITCZ...

A monsoon trough enters the Atlantic near the coastal border of
Guinea and Guinea-Bissau, then curves southwestward to 03N19W. 
An ITCZ continues from 03N19W across 00N26W to the coast of 
Brazil, northwest of Natal. Scattered moderate convection is 
noted up to 120 nm along either side of the ITCZ. 

...GULF OF AMERICA...

Please read the Special Features section about very rough seas.

A strong cold front extends southwestward from the Florida Straits
to the Yucatan Peninsula. Scattered showers and thunderstorms are
occurring up to 80 nm along either side of this front, including
the Yucatan Channel. Moderate to fresh N winds and seas of 5 to 8
ft are present north of 25N. South of 25N except waters off 
Veracruz, fresh to strong N to NE winds with 9 to 13 ft seas are 
noted. Strong to near gale- force NW to N winds and seas at 12 to 
16 ft persist off Veracruz.

For the forecast, once the front has moved over Cuba and the
northwestern Caribbean later this morning, winds and seas in the
Gulf of America will gradually decrease this afternoon and 
evening, except for the southeastern Gulf, where moderate to 
strong N to NE winds will linger until late this evening. Rough 
to very rough seas behind the front will gradually subside from 
north to south today through this evening. In the wake of the 
front on Wed, high pressure will build across the region and 
prevail into the weekend. 

...CARIBBEAN SEA...

Convergent southerly trade winds are triggering scattered showers
and isolated strong thunderstorms between southeastern Cuba and
Jamaica. Recent scatterometer and altimetery satellite data 
confirmed fresh to strong E winds with 8 to 10 ft seas across the 
eastern and central basin. These winds are supported by strong 
high pressure over the central Atlantic. Moderate with locally 
fresh E to SE winds and seas of 4 to 7 ft are noted elsewhere 
across the basin.

For the forecast, the aforementioned high pressure will support 
fresh to strong trade winds and rough seas across the waters near 
the Lesser Antilles, and the eastern and central Caribbean, 
including the Atlantic exposures and Passages through Wed. Later 
this morning, a cold front is expected to enter the northwestern 
Caribbean from the Gulf of America. Then, it will slow down and 
possibly stall from western Cuba to the Gulf of Honduras by early 
Wed morning while dissipating. This should decrease the influence 
from the ridge and allow winds and seas across the central and 
eastern Caribbean to gradually subside through Sat. 

...ATLANTIC OCEAN... 

A strong cold front extends southwestward from off the Carolina 
coast across 31N76W to beyond southern Florida. Scattered 
moderate to isolated strong convection is flaring up near and up 
to 200 nm southeast of this feature. At the eastern Atlantic, a 
weakening cold front curves southwestward from just south of the 
Azores across 30N30W to near 27N50W. Scattered showers are seen up
to 50 nm along either side of this boundary. Well to the south, 
modest convergent trades are generating scattered moderate 
convection near the coast of Brazil from Sao Luis westward to near
the Amazon River Delta area. Refer to the Monsoon Trough/ITCZ 
section for additional convection in the Atlantic Basin.

Fresh to S to SW to NW winds with 8 to 10 ft seas are seen behind
and ahead of the first cold front, north of 25N and west of 60W.
To the east and south, fresh to strong NE to SE winds and seas of
8 to 11 ft in large mixed swells dominate north of 20N between 35W
and 60W, and from 20N to 25N west of 60W. For the tropical
Atlantic from 05N to 20N between 40W and the Lesser Antilles,
fresh to strong NE to E winds and 8 to 10 ft seas are evident. For
the remainder of the Atlantic Basin west of 35W, moderate to
locally fresh NE winds and seas at 6 to 8 ft prevail. 

For the forecast west of 55W, fresh to strong winds along with 
rough seas will shift eastward with the first front through Wed 
morning. By Wed afternoon, the front will stall from near Bermuda 
to the central Bahamas while weakening. This should allow winds 
and seas north of 26N to gradually decrease during the second half
of the week. In response to this front, fresh to strong E to SE 
winds and rough seas currently from 18N to 25N, including the 
central and southeast Bahamas should slowly subside Wed afternoon 
through Thu morning.

$$

Chan