Marine Interpretation Message
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26
000
AGXX40 KNHC 120722
MIMATS

Marine Weather Discussion
NWS National Hurricane Center Miami FL
222 AM EST Tue Dec 12 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...

High pressure over the W central Gulf controls the weather across
the basin, while a developing cold front is located to the NW-N
moving into the lower Mississippi Valley states. Gentle winds are
across the central Gulf under an eastward extending ridge axis
from the high, and mainly moderate winds elsewhere, except in the
N central Gulf where the pressure gradient is locally tighter.
Seas are mainly 1-3 ft, except up to 4 ft near the Straits of
Florida and Yucatan Channel.

The high will shift eastward as the developing cold front
approaches and enters the N central and NE Gulf shortly after
sunrise this morning. Winds will shift to W-NW while increasing
to fresh to strong behind the front, with seas building to 8 ft
as a result through the afternoon. The front will continue to
race SE extending from near Fort Myers, Florida to the central
Gulf along 25N by this coming evening. The front will move SE of
the basin through Wed morning with high pressure re-building in
its wake.

A ridge axis will again extend across the central Gulf by Wed
evening with winds gentle and 1-3 ft across the basin, except 4-5
ft in the SE portion due to residual NW swell behind the front.
The ridge will shift eastward ahead of the next cold front which
is forecast to move into the NW waters by Thu evening. This next
front will also race SE extending from the Florida Panhandle to
the central Gulf near 26N91W to near Tampico, Mexico by Fri
morning, from SW Florida to Veracruz, Mexico Fri evening, exiting
the basin to the SE by Sat evening. Winds will shift to NW-N and
increase to fresh to strong with seas building to 5-8 ft behind
the front.

Conditions will improve by Sat morning as high pressure settles
across the southern U.S. Gulf coast states. The high will then
slide eastward for the end of the weekend allowing for return
flow to dominate the basin ahead of the next potential cold
front.

...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN
55W AND 64W...

A stationary front extends from near the Windward Passage to just
SE of Jamaica to western Panama. Active convection remains near
the boundary S of Jamaica and W of the front. A recent
scatterometer pass showed fresh to near gale force northerly
winds W of the front to around 18N83W, with seas of 7-11 ft.
Meanwhile, moderate trades and 2-4 ft seas prevail E of the
front, except 4-7 ft W of 72W.

The front will remain nearly stationary through mid-week while
gradually dissipating to a remnant trough by the end of the week.
The fresh to strong winds will persist just W of the front,
finally diminishing Thu as the front dissipates. Once the front
dissipates, the pressure gradient will tighten allowing for fresh
to strong trades in the S central Caribbean by Thu evening,
strongest to near gale force just NW of the coast of Colombia by
Fri night. The pressure gradient will continue to tigthen during
the upcoming weekend with gale conditions possible NW of the
coast of Colombia by Sat night.

Meanwhile, another cold front will approach the NW Caribbean by
Wed afternoon, but will likely dissipate before it makes much
progress into the basin. The next cold front after that is
forecast to move into the NW portion Fri night, stalling and
gradually dissipating from near eastern Cuba to the Gulf of
Honduras during the upcoming weekend.

...SW N ATLANTIC INCLUDING THE BAHAMAS...

A stationary front extends from near 27N65W to across the Turks
and Caicos to the Windward Passage, with a ridge axis analyzed
from SE Florida to 1018 mb high pressure near 31N70W. A recent
scatterometer pass showed fresh to locally strong N-NE winds just
W of the front to the S of 27N, with gentle to moderate winds
near the ridging. Seas are 6-8 ft in the area of stronger winds,
with 3-5 ft elsewhere across the basin outside of the Bahamas.
Meanwhile, SW flow is developing offshore of NE Florida ahead of
the next cold front.

That next front will continue to approach through the morning and
afternoon, with SW flow increasing to fresh to strong during the
afternoon. The front will move into the NW waters by this coming
evening with winds increasing to near gale force, with a gale
warning in effect from 31N northward. Shifting W-NW strong to
near gale force winds will also follow the front, spreading
across the entire waters N of 27N tonight. The front will extend
from near Bermuda to the Straits of Florida by early Wed
afternoon with conditions improving under ridging in its wake.

The ridge will extend from SE Florida to 27N70W Wed night before
weakening as the next cold front approaches by Thu morning. Fresh
to strong winds will precede the next front N of 29N by Thu
morning, but will diminish through the day as this next front
remains primarily N of 31N.

A stronger front will approach by Fri morning with SW flow
increasing back to fresh to strong N of 27N by Fri afternoon.
That front will move into the NW waters by Fri evening with winds
both ahead of and behind the front possibly increasing to gale
force. That front will race eastward extending from near 31N68W
to central Cuba by Sat morning, then dissipating as it lies down
from near 25N65W to eastern Cuba late Sat night.

$$

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

.GULF OF MEXICO...
     None.

.CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN
55W AND 64W...
.AMZ031...CARIBBEAN FROM 11N TO 15N BETWEEN 72W AND 80W
INCLUDING COLOMBIA BASIN...
     GALE CONDITIONS POSSIBLE Sat night.

.SW N ATLANTIC INCLUDING THE BAHAMAS...
.AMZ111...ATLANTIC FROM 27N TO 31N W OF 77W...
     GALE CONDITIONS POSSIBLE Fri night.
.AMZ113...ATLANTIC FROM 27N TO 31N BETWEEN 70W AND 77W...
     GALE CONDITIONS POSSIBLE Fri night.
.AMZ115...ATLANTIC FROM 27N TO 31N BETWEEN 65W AND 70W...
     GALE CONDITIONS POSSIBLE Fri night into Sat.

$$

*For detailed zone descriptions, please visit:
http://www.nhc.noaa.gov/abouttafbprod.shtml#OWF

Note: gridded marine forecasts are available in the National
Digital Forecast Database (NDFD) at:
http://www.nhc.noaa.gov/marine/grids.php

For additional information, please visit:
http://www.nhc.noaa.gov/marine

$$

.Forecaster Lewitsky. National Hurricane Center.


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.