AGXX40 KNHC 200723
Marine Weather Discussion
NWS National Hurricane Center Miami FL
323 AM EDT Fri Oct 20 2017
Marine Weather Discussion for the Gulf of Mexico, Caribbean Sea,
and Tropical North Atlantic from 07N to 19N between 55W and 64W
and the Southwest North Atlantic including the Bahamas
...GULF OF MEXICO...
A surface trough is in the SW corner of the area, hugging the
coast, from the northern part of the Isthmus of Tehuantepec of
southern Mexico, to 23N97W. Broad surface anticyclonic wind flow
spans the rest of the Gulf of Mexico. High pressure across SE US
will move slowly ENE-to-NE and into Atlc through the weekend.
Expect fresh wind flow across the NE and N central sections,
with winds gradually veering through Sun. Light to moderate Sly
flow is expected just ahead of a cold front, that is forecast to
be exiting the TX coast late Sun night. The front will reach the
central Gulf waters on Mon with fresh to locally strong N flow W
of the front.
...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN
55W AND 64W...
Two tropical waves will continue across the central and western
sections of the Caribbean Sea today and tonight, and across the
western sections and parts of Central America and the eastern
Pacific Ocean, from Fri through Sun. Fresh to strong E-to-ESE
trades, with 7-11 ft seas prevail across the basin E of 75W attm
as strong E Atlc ridge has built WSW almost to the Bahamas.
Strong trades extend well E of the Lesser Antilles to 55W-56W,
where seas have been in the range of 8-12 ft per altimeter data
during the last 24 hours. These conditions will shift W and
expand slowly across the central Carib during the next 48 hours,
with seas building to 8-13 ft. Wind speeds will diminish
slightly across the Tropical N Atlc waters. Sufficient fetch will
maintain 7-10 ft sea heights. The ridge will weaken and shift NE
as the frontal system moves into central Atlc during the weekend.
High pressure building off E coast of US behind front will
reinforce pres gradient across the basin through the weekend to
maintain rough conditions.
...SW N ATLANTIC INCLUDING THE BAHAMAS...
Cold front through 31N67W to 29N70W to 27N73W. Stationary front
from 27N73W to 25N78W. Dry air is covering the area that is
behind the frontal boundary. The wind speeds that are to the NW
of front are in the 20 kt range, from 26N to 30N from 76W
westward, with seas 7-10 ft. Ridge to the E and SE of front
producing moderate to fresh SE to S winds E of the front.
Weak low to develop along front today near 31N70W and is
producing gales already N of the local area, and forecast to
deepen and expand as it moves NE next 2 days and drags frontal
remnants ESE. Sufficient pres gradient to persist across NW
waters to maintain fresh NE to E wind and seas 6-7 ft through the
weekend and veering to the SE Sun and Mon. E trades to freshen
through Srn Bahamas to Cuban coast during that time.
.WARNINGS...Any changes impacting coastal NWS offices will be
coordinated through AWIPS II Collaboration Chat, or by
.GULF OF MEXICO...
.CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN
55W AND 64W...
.SW N ATLANTIC INCLUDING THE BAHAMAS...
*For detailed zone descriptions, please visit:
Note: gridded marine forecasts are available in the National
Digital Forecast Database (NDFD) at:
For additional information, please visit:
.Forecaster MT. National Hurricane Center.