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AGXX40 KNHC 231840

Marine Weather Discussion
NWS National Hurricane Center Miami FL
240 PM EDT Mon Oct 23 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


A cold front extends from the Florida panhandle near 30N86W to
the bay of campeche near 20N95W to the vicinity of tampico Mexico
near 23N98W. The forecast still retains a developing gale along
the SW Gulf coast for the waters near Veracruz Mexico. Latest
forecast issuance trends the current event downward in agreement
with model guidance in keeping a minimal gale in the forecast
from 18Z to 00Z this evening. A repeat performance is anticipated
for tomorrow evening, as a reinforcing shot of cold air will
increase the pressure gradient over the Gulf and aid in the mix
down of momentum from aloft. The secondary surge of cold air will
bring 20 to 25 kt winds to almost all of the Gulf from Tuesday
evening until around midday on Wed. The front will move from the
gulf into the NW Caribbean by dawn on Wed. Winds and seas in the
basin will subside Wed night and Thu as high pres builds over the
northern Gulf.

55W AND 64W...

A tropical wave is located to the east of the Windward islands
along 55W/56W. The wave is being sheared and weakened by a strong
mid to upper-level trough which extends south into the NE
Caribbean along 65W. Upper-level divergence associated with the
rough is causing deep convection to flare within 180 nm east and
within 360 nm west of the wave axis. Fresh to locally strong
trade winds to the east of the wave axis are expected to maintain
an area of 8 ft seas east of the Windwards generally between 09N
and 14N between 45W and 55W through Friday. The tropical wave is
expected to continue weakening and survive at lower latitudes as
it progresses westward.

Broad low pressure over the SW Caribbean near the eastward
extension of the monsoon trough from the eastern Pacific is
combining with a western Atlantic Ocean ridge to generate a large
area of fresh to strong winds and seas of 8 to 11 ft in almost
all of the central Caribbean. The winds and seas will diminish by
Tue afternoon as a cold front heading SE from the United States
weakens the ridge. The front will enter the NW Caribbean on Wed
morning, then stall on Thursday. Funneling of winds between the
front and the Yucatan will generate an area of strong winds and
seas to 8 ft or above Wed morning through Thursday morning.
Models are trending upward with winds and seas in this area so
this area so there is a potential for a minimal gale over the far
western Caribbean during this time frame. Prevailing winds over
the Caribbean Sea are expected to remain light to moderate on Thu
and Fri, with a weak ridge remaining in place to the north. Low
pressure is expected to develop within a surface trough over the
western Caribbean Sea by Friday.


High pres centered over the W Atlc near 43N61W will maintain
fresh to locally strong E to SE winds, especially S of 22N today.
A cold front will move SE from the Carolinas and Florida Tuesday
morning. Strong S winds and seas building to 8 ft can be
expected just N of the discussion area, or N of 31N W of 75W
around dawn. The front may be accompanied by a line of showers
and thunderstorms capable of producing strong gusty winds and
rough seas. The front will weaken as it moves SE Wed through Thu
night. A round of NE swell generated to the N of a weakening
front over the central Atlc will cause seas to build to 8 ft
near 31N65W on Wed. High pressure is expected to slide NE from
the Gulf of Mexico, along the SE coast of the United States
Friday and Saturday, supporting light to gentle winds and seas
of 4 to 5 ft east of the Bahamas.


.WARNINGS...Any changes impacting coastal NWS offices will be
coordinated through AWIPS II Collaboration Chat, or by

.GMZ023...SW GULF S OF 22N W OF 94W...
     Gale Warning today.
     Gale Warning Tue.
     GALE CONDITIONS POSSIBLE Sat into Sat night.

55W AND 64W...



*For detailed zone descriptions, please visit:

Note: gridded marine forecasts are available in the National
Digital Forecast Database (NDFD) at:

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