Tropical Weather Discussion
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AXNT20 KNHC 200605

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
105 AM EST Tue Feb 20 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 0000 UTC surface analysis and satellite imagery through
0530 UTC.


Caribbean Sea Gale Warning: A tight surface pressure gradient
continues between high pressure in the western Atlantic and
lower pressure in northern sections of South America. This
pattern will support winds pulsing to minimal gale-force near
the coast of Colombia each night this week. Wave heights within
the area of gale force winds will range between 12-16 ft. Please
read the latest NHC High Seas Forecast under AWIPS/WMO headers
MIAHSFAT2/FZNT02 KNHC for more details.


The monsoon trough axis extends from the coast of Africa near
07N12W southwestward to 01N20W. The ITCZ crosses the equator
near 21W and remains south of the discussion area to the coast
of South America. Scattered moderate convection is from 00N-05N
between 11W-30W.



A surface ridge extends westward across the entire basin from
the Atlantic. Scatterometer data depicts moderate southeasterly
winds across most of the area. Satellite imagery shows isolated
shallow convection in the SE Gulf and fair weather elsewhere.
Expect increasing winds and building seas through Wed as high
pressure strengthens in the western Atlantic. A thermal trough
will develop over the western Yucatan Peninsula each evening
through mid week, drift westward across the Bay of Campeche
during overnight hours, then dissipate in the SW Gulf by late


Please refer to the SPECIAL FEATURES section for details about
a Gale Warning in effect near the coast of Colombia.

A tight pressure gradient across the basin created by the
combination of strong high pressure over the Atlantic and lower
pressure over NW Colombia is producing strong east winds between
70W-80W, while moderate to fresh winds prevail elsewhere. Trade
wind showers are evident from satellite imagery primarily east
of 70W. The high pressure will strengthen through Wednesday,
increasing the winds and building seas east of 80W in the
Caribbean and the Tropical N Atlantic waters through mid-week.


A cold front extending from 32N40W to 28N48W to 27N56W becomes
diffuse west of 60W. Scattered moderate showers are observed
along a pre-frontal trough, and low clouds with scattered light
rain are evident along the frontal boundary. Broad high pressure
centered north of 30N prevails across the rest of the basin. The
front will become stationary during the next 12 hours and should
dissipate later today. The existing area of high pressure will
be fortified by a stronger subtropical high through mid-week.

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