Tropical Weather Discussion
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000
AXNT20 KNHC 230000
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
705 PM EST Mon Jan 22 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 1800 UTC surface analysis and satellite imagery through
2330 UTC.

...SPECIAL FEATURES...

Caribbean Gale Warning: The combination of high pressure in the
central Atlantic and lower pressures over northern Colombia will
allow trades in the SW Caribbean near the coast of Colombia to
increase to minimal gale force late tonight and Tue morning then
subside back to strong by noon. Seas are expected to build to 10
to 13 ft with these winds. Winds are expected to pulse back to
gale force again late Tue night into Wed morning. Model guidance
indicates that the pulsing to minimal gale will continue through
the rest of the week. Please see latest NHC High Seas Forecast
under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details.

Gulf of Mexico Gale Warning: Gale force winds are forecast to
commence Tue afternoon in the SW Gulf behind a cold front that
is across the NW Gulf coast this evening. The cold front will
reach from the Florida Big Bend to the eastern Bay of Campeche
tonight, and from Straits of Florida across Yucatan Peninsula to
Veracruz Mexico on Tue night, then move SE of the area on Wed.
Minimal gale force NW to N winds are likely near the coast of
Veracruz Tue afternoon, then diminish to strong winds Tue night.
Gale force winds may return briefly to the same area Wed night,
then diminish significantly on Thu. Please see the latest NHC
High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC
for more details.

...MONSOON TROUGH/ITCZ...

The monsoon trough axis extends from western Africa near 06N09W
to 01N19W. The ITCZ begins near 01N19W and extends to 02N32W to
South America near 01N49W. Scattered moderate isolated strong
convection is within 120 nm N of the ITCZ between 33W-35W.
Scattered moderate convection is elsewhere within 180 nm N of
the axis between 33W-35W, and within 30 nm either side of a line
from 02N25W to 03N30W.

...DISCUSSION...

...GULF OF MEXICO...

A cold front extends from New Orleans, Louisiana to 23N98W in
eastern Mexico. Scattered showers and isolated thunderstorms are
along a squall line just ahead of the front. Behind the front,
conditions rapidly dry out in strong high pressure centered over
northern Texas. The cold front will reach the far SE Gulf waters
on Tue night, and move to SE of the area on Wed. The gradient
associated with the aforementioned strong high pressure will
support fresh to strong northerly winds over much of the Gulf
through Wed.

...CARIBBEAN SEA...

Diffluence aloft supports isolated showers and few thunderstorms
over portions of the NW Caribbean. Fresh to strong winds were
noted in the latest scatterometer data over much of the central
Caribbean, with the strongest winds near the coast of Colombia.
Moderate to locally fresh trades are noted elsewhere across the
basin. The pressure gradient provided by high pressure N of the
area should allow for fresh to strong NE to E trades to occur W
of about 70W elsewhere through late Wed night. Strong NE winds
are expected through the Windward Passage after Wed. A cold
front in the Gulf of Mexico will enter the NW Caribbean Wed
night, followed by increasing strong NE winds and seas building
to around 10 ft.

...ATLANTIC OCEAN...

Ridging dominates the western Atlantic anchored by high pressure
centered near 31N60W, with a ridge extending westward into the
Gulf of Mexico. A robust mid/upper level trough is evident on
water vapor imagery extending from a cyclonic circulation near
33N64W to eastern Cuba. Scattered showers and few thunderstorms
are north of Hispaniola to 25N, and from 20N to 26N between 65W
and 70W. Isolated showers are elsewhere N of 19N between 60W and
70W. A stationary front is located over the E central Atlantic
from near 32N38W to 26N43W to 24N46W. Divergence aloft E of the
upper level cyclonic circulation is helping to trigger scattered
showers and thunderstorms from 24N to 28N between 37W and 40W.
Expect shower activity to expand eastward through Wed ahead of
the trough to 50W. A cold front will move off the NE Florida
coast on Tue afternoon, and reach from near 31N73W to Straits of
Florida on Wed morning, and from Bermuda to central Cuba on Thu
morning. Strong NE winds under high pressure will follow behind
the front. Numerous showers and isolated thunderstorms with
gusty winds will precede the front.

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

$$
Mundell



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