[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 111203
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
702 AM EST Sun Feb 11 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
1200 UTC.

...SPECIAL FEATURES...

Caribbean Sea Gale Warning: A tight surface pressure gradient
between the strong surface ridge over the north Atlantic Ocean
and lower pressures over northwestern South America will continue
to support gale-force winds pulsing near the coast of Colombia
through the next week, mainly at night. Please read the latest NHC
High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC
for more details.

...MONSOON TROUGH/ITCZ...

The monsoon trough enters the Atlantic through the coast of
Liberia near 05N10W and continues to 01S22W. The ITCZ begins near
01S22W and extends to the coast of Brazil near 05S37W. Scattered
showers are within 100 nm on either side of the ITCZ.

...DISCUSSION...

GULF OF MEXICO...

A ridge extending from the north-central Atlantic through the
central Gulf supports moderate southerly winds, except for
moderate to fresh winds in the north-central Gulf N of 26N and
north of the Yucatan Peninsula to 23N. Upper level diffluent flow
and moisture inflow from the Caribbean support scattered moderate
convection within 50 nm off the coasts of Mississippi, Alabama
and the Florida Panhandle. The moist southerly flow continue to
support dense fog over the northwest Gulf N of 26N with 3 NM
visibilities over offshore areas. A cold front is along the Texas
coastline and will move off the coast later this morning. The
front will reach from southeast Louisiana to near Brownsville,
Texas by this evening, and from the western Florida Panhandle to
the western Bay of Campeche by Mon evening, where it will stall
and weaken. Fresh to strong northerly winds and building seas to 8
ft will follow the front Sun night and Mon. Looking ahead, winds
and seas will diminish into Tue as a ridge develops over the
southeast United States. This pattern will support fresh east
winds by mid week.

CARIBBEAN SEA...

Please read the SPECIAL FEATURES section for details about the
gale-force wind conditions expected near the coast of Colombia.

GOES-16 water vapor imagery continues to show deep layer stable,
dry air across most of the basin, which is supporting generally
fair weather conditions. Strong high pressure north of the area
continues to support fresh to strong trade winds across the
eastern and central Caribbean, as noted in recent scatterometer
satellite data. Seas are reaching 8 to 12 ft, except near the
Colombia coast where seas will be up to 16 ft. The areal extent
of the strong trade winds and associated seas will spread westward
through mid week, including the Windward Passage and lee of Cuba.
Otherwise, little change is expected.

ATLANTIC OCEAN...

Broad surface ridging anchored N of the area by a 1044 mb high
near 43N47W and a 1038 mb high southwest of the Azores near
36N40W extends across the basin. The ridge is supporting moderate
to fresh east to southeast flow over most of the SW N Atlantic,
except for strong trade winds south of 23N with 8 to 10 ft seas.
Farther east over the central Atlantic, a surface trough extends
along 45W from 18N to 27N. Scattered showers associated with it
are from 17N to 25N between 38W and 48W. The surface trough
weakens the gradient enough to support mainly moderate to fresh
trade wind flow across the central tropical Atlantic, but seas
remain 8 to 12 ft in easterly swell. A cold front will move off
the northeast Florida coast by Tue afternoon, followed by fresh
northerly flow and building seas north of the Bahamas, then
diminish through mid week as the front stalls and dissipates. Over
the eastern Atlantic, moderate to fresh northeast winds dominate
this region of the Atlc, except for strong winds north of the Cape
Verde islands. The long duration and fetch of these strong winds
support fully developed seas of 8 to 11 ft. Jet dynamics aloft is
supporting a broad area of multi-level clouds with possible
embedded showers between 20W and 43W, including the Cabo Verde
Islands.

For additional information please visit
http://www.hurricanes.gov/marine

$$

ERA/NR
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