Tropical Weather Discussion
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AXNT20 KNHC 211204

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
704 AM EST Wed Feb 21 2018

Tropical Weather Discussion for North America, Central America
Gulf of Mexico, Caribbean Sea, northern sections of South
America, and Atlantic Ocean to the African coast from the
Equator to 32N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 0600 UTC surface analysis and satellite imagery through
1130 UTC.


Caribbean Sea Gale Warning: Strong high pressure over the western
Atlc and low pressure over South America are combining to maintain
a tight surface pressure gradient over the Caribbean. This
pattern is supporting winds reaching gale force strength along the
coast of Colombia from 10N to 13.5N between 73W and 77.5W. Wave
heights within the area of gale force winds are currently ranging
between 10 feet and 16 feet. This synoptic setup is expected to
remain in place through Fri morning. Please read the latest NHC
High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC
for more details.


The monsoon trough passes through coastal sections of Sierra
Leone near 08N13W to 06N16W. The ITCZ continues from 06N16W,
crossing the Equator near 22W, to 02S32W, to near the coast of
Brazil near 03S39W. Convection: Scattered moderate and isolated
strong convection is present from 02N to 05N between 06W and 12W.
Scattered moderate convection is noted from 01S to 02N between 17W
and 25W and from 04S to 00N between 27W and 37W.



Upper level SSW wind flow is moving from southern Mexico, across
Texas and Louisiana and the Gulf of Mexico W of 95W. Broad upper
level ridging dominates the basin and is currently suppressing
convection over all of the basin except along the upper Texas

Strong surface high pressure across the W Atlantic Ocean will
persist, with a ridge extending W across the U.S.A. Gulf coast
states, in order to produce fresh return flow across most of the
basin, except for strong winds through the Straits of Florida and
across central sections of the Gulf. A weak cold front will move
slowly into the far NW waters on Sunday, and stall there on Sunday


Please read the SPECIAL FEATURES section for details about the
Gale Warning for the waters that are near the coast of Colombia.

A surface ridge passes across central Cuba, to 19N82W in the NW
corner of the area, to southern Costa Rica.

Surface high pressure across the NW Atlantic Ocean will build S
across the region through Wednesday, and then settle across the
Bermuda area through the end of the week. Fresh-to-strong trade
winds will prevail across the Caribbean Sea and the Tropical N
Atlantic waters through Thursday, with nocturnal winds pulsing to
gale-force off the coast of Colombia. High pressure will weaken
through the weekend, leading to diminishing winds and seas.


An upper level trough passes through 32N34W to 23N53W to 24N48W,
to 19N60W. A cold front passes through 32N30W, to 23N40W and
21N53W. A dissipating cold front continues from 21N53W to 21N62W.
Broken to overcast low level clouds and possible rainshowers are
to the NW and N of the line that passes through 32N27W 22N40W
18N60W 18N68W.

A surface ridge passes through 32N68W, beyond central Cuba, into
the NW corner of the Caribbean Sea.

A W Atlantic Ocean ridge will persist along 33N-34N through
Thursday, and then it will drift SW, and slowly weaken through the
weekend. Gentle-to-moderate winds will prevail N of 25N, with
fresh-to-strong winds S of 25N through Thursday. NNE swell will
move through the waters E of 65W through Friday night.

For additional information please visit

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