Tropical Weather Discussion
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000
AXNT20 KNHC 051205
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
705 AM EST Tue Dec 5 2017

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
1115 UTC.

...SPECIAL FEATURES...
...GALE-FORCE WINDS IN THE ATLANTIC OCEAN...
A middle level to upper level central Atlantic Ocean trough is
supporting a 997 mb storm center, near 35N53W. A cold front is
part of the entire weather system, passing through 32N50W, to
29N57W, and 28N64W. Rainshowers are possible from 24N north from
45W westward. The forecast for the next 24 hours consists of W-to-
NW gale-force winds, and sea heights ranging from 14 feet to 23
feet, from 27N northward between the front and 59W.ATLC COLD
FRONT FROM 31N51W TO 28N58W TO 28N63W. N OF 30N W OF FRONT TO 59W
W TO NW WINDS 30 TO 35 KT. SEAS 14 TO 17 FT. Please read the
latest NWS High Seas Forecast under AWIPS/WMO headers
MIAHSFAT2/FZNT02 for more details.

...ITCZ/MONSOON TROUGH...
The monsoon trough passes through the coastal sections of Sierra
Leone near 08N13W to 07N18W. The ITCZ continues from 07N18W to
04N30W to 02N47W. Precipitation: isolated moderate to locally
strong rainshowers are within 150 nm on either side of 06N11W
05N20W 05N34W 05N48W 07N57W.

...DISCUSSION...

THE GULF OF MEXICO...

Broad middle level to upper level NW wind flow and comparatively-
drier air in subsidence span the entire Gulf of Mexico.

A surface ridge passes through NW Florida, into the SW corner of
the Gulf of Mexico.

...CURRENT CONDITIONS AND WEATHER, FOR THE OFFSHORE OIL PLATFORM
SITES, THAT ARE IN THE AREA WHOSE BOUNDARIES ARE FROM 27N
NORTHWARD AND FROM 88W WESTWARD...

LIFR: none. IFR: none. MVFR: KBBF, KBQX, KGUL, KATP, KVOA,.

CURRENT CONDITIONS AND WEATHER, FOR THE COASTAL PLAINS OF THE
U.S.A., FROM THE DEEP SOUTH OF TEXAS TO FLORIDA...

TEXAS: LIFR and fog from the middle Texas Gulf coast southwestward
to the Laredo area. MVFR-to-IFR in the deep south of Texas, and
elsewhere in some parts to the north and northeast, away from the
middle Texas coast area. LOUISIANA: LIFR and fog in the deep
south. MISSISSIPPI: a mixture of IFR and MVFR in the south and
coastal plains. ALABAMA: conditions range from IFR to MVFR in the
southern and coastal areas. FLORIDA: LIFR to MVFR from Cross City
westward.

THE CARIBBEAN SEA...

Large scale upper level anticyclonic wind flow moves through the
SW corner of the area, toward Hispaniola, and then curving toward
the east and southeast.

Middle level-to-700 mb NE wind flow covers the area that is from
14N northward between 68W and 80W. Middle level-to-700 mb E wind
flow covers the area that is from 15N northward from 80W westward.

Middle level-to-700 mb level cyclonic wind flow is under upper
level SW wind flow, in the SW corner of the Caribbean Sea. The
monsoon trough is in the eastern Pacific Ocean along 06N/07N
between 79W and beyond 86W. Precipitation: isolated moderate to
locally strong from 16N southward between 73W to the coast of
Nicaragua.

A surface trough is in the SE corner of the Caribbean Sea, along
16N60W 13N61W, toward NE Venezuela and Trinidad. Precipitation:
isolated moderate to locally strong rainshowers are from 14N to
17N between 57W and 68W.

24-hour rainfall totals in inches, for the period that ended at
05/0000 UTC, according to the PAN AMERICAN TEMPERATURE AND
PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...are: 0.06 in
Curacao.

...HISPANIOLA...

Upper level NW wind flow is moving across the area. Large scale
upper level anticyclonic wind flow moves through the SW corner of
the area, toward Hispaniola, and then curving toward the east and
southeast.

SURFACE OBSERVATIONS...VFR for Port-au-Prince in Haiti. in the
DOMINICAN REPUBLIC: Puerto Plata: MVFR. ceiling 1700 feet. VFR,
elsewhere.

The GFS MODEL forecast for 250 mb shows that a ridge will start
along the line from Colombia to the offshore waters of eastern and
central Honduras. Expect SW wind flow during day one. The SW wind
flow will become westerly during day two. The GFS MODEL forecast
for 500 mb shows that anticyclonic wind flow at the start of the
48-hour forecast period will switch to NW, with a developing
east-to-west oriented trough. A col point will end up in the
central sections of the Dominican Republic. A NE-to-SW oriented
trough will develop to the east of the col point, and SE-to-NW
oriented trough will develop to the west of the col point.
The GFS MODEL forecast for 700 mb shows that day one will start
with SE wind flow across the area, changing to cyclonic wind flow
in Haiti, and anticyclonic wind flow in the Dominican Republic,
and eventually NE wind flow at the end of day one. An anticyclonic
circulation center will be just off the SE coast of Cuba at the
end of day one. An inverted trough will persist across Hispaniola
during day two.

THE ATLANTIC OCEAN...

An upper level trough passes through 32N30W to 24N27W. The trough
supports a cold front that passes through 32N29W 27N38W. A
stationary front continues from 27N38W to 24N50W and 22N60W. A
shear axis continues from 22N60W to 21N67W, to the waters that are
just to the west of Haiti near 19N74W. Precipitation: isolated
moderate rainshowers within 150 nm on either side of the line
that passes through 32N24W, 31N36W, 25N47W, to 21N75W.
Part of this precipitation is in the waters that are to the north
of the Greater Antilles and the NE Caribbean Sea islands.

A surface trough is along the coast of Africa and into the Western
Sahara, passing through 32N11W, through the eastern parts of the
Canary Islands, to 20N18W. No significant deep convective
precipitation is apparent in satellite imagery.

A surface ridge passes through 32N18W to 29N23W to 23N32W, to
20N45W and 20N63W.

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

$$
MT



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