Marine Interpretation Message
Issued by NWS
AGXX40 KNHC 230502
Marine Weather Discussion
NWS National Hurricane Center Miami FL
102 AM EDT Thu Mar 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
...GULF OF MEXICO...
A surface high analyzed at 27N93W just before sunrise this
morning will shift n of the area later this morning with the
pressure gradient tightening across the entire gulf waters this
afternoon. A thermal trough will develop late each afternoon
over the Yucatan Peninsula, and shift w across the southern
waters, generally to s of 23N between 90W and 93W, during the
overnight hours, and gradually lose identity along about 94W
late each morning. Expect a ne-e-se 20-25 kt wind shift along
the trough axis, with seas building to 7 ft. Fresh to strong
easterly breezes will develop elsewhere tonight with an embedded
swath of near gale force se winds...and seas to 9 ft...near
27N95W just before sunrise on Fri. The pressure gradient will
relax on Fri with fresh se to s flow forecast everywhere by Sat
morning. A moderate to locally fresh easterly breeze forecast
across the southern gulf waters on Sun. Small patches of strong
southerly flow is forecast along the coast of Central Mexico on
Sun afternoon, as well as developing along the n coast of the
Yucatan Peninsula on Sun evening. The pressure gradient should
relax some more on Mon, with only a fresh breeze expected along
the n coast of the Yucatan on Mon evening.
...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN
55W AND 64W...
Fresh ne winds currently to the lee of Cuba will diminish a
moderate breeze today, with freeze ne breezes redeveloping this
evening with a strong ne breeze also developing in and
downstream of the Windward Passage on Thu. Expect this strong ne
flow to continue across the n-central and the nw Caribbean on
Fri. The pressure gradient is forecast to relax on Sat, but
still expect strong ne pulses to the lee of Cuba on Sat and Sun
nights. Large n swell will reach the n Caribbean Passages late
Fri night, and continue through early Sun before subsiding.
Strong ne nocturnal winds expected within 90 nm of the nw coast
of Colombia tonight.
Fresh trades forecast across the tropical waters e of the
Leewards tonight with seas building briefly to 8 ft.
...SW N ATLANTIC INCLUDING THE BAHAMAS...
A warm front extending from 28N55W to 27N65W to 22N72W will
continue to move nw and merge with a cold front today that
currently extends from 31N70W to 27N80W. The merged front will
weaken to a frontal trough on Fri and then drift n on Sat with a
surface low developing along the trough near 22Nn69W on Sun. The
low should reach near 24N68W on Mon. Strong to near gale force
post-frontal ne winds will spread se across the entire area with
10 to 15 ft seas propagating s across the waters e of the
Bahamas late tonight into Fri. Guidance has been fluctuating
with the areal extent of these near gale force winds. If
guidance becomes more consistent, a gale warning may have to be
issued mainly for frequent gusts to gale force. There is much
uncertainty with the low pressure development, its strength and
eventual track. There is a slight possibility of near gale
force, or even minimal gale conditions over the n semicircle of
the low as early as Sun afternoon.
Anyway, the large seas will subside from the n beginning on Fri
night, but still expect strong to near gale force e winds, and 8
to 14 ft seas to the s of 28N on Sat afternoon, and strong e
winds and 8 to 11 ft seas e of the Bahamas on Sun afternoon.
Winds should diminish to a moderate e breeze late Mon night.
.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 Nelson. National Hurricane Center.