[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 310604
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
103 AM EST SAT DEC 31 2016

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
0515 UTC.

...SPECIAL FEATURES...

...Caribbean Sea Gale Warning...

The 30-hour forecast, starting at 31/0000 UTC, consists of:
NW gale-force winds, and sea heights ranging from 9 feet to 13
feet, from 11N to 13N between 73W and 76W. Please read the HIGH
SEAS FORECAST...MIAHSFAT2/FZNT02 KNHC...and the OFFSHORE
FORECAST...MIAOFFNT3/FZNT23 KNHC...for more details.

...THE MONSOON TROUGH/THE ITCZ...

The Monsoon Trough passes through the coastal sections of Liberia
near 06N11W, to 04N14W. The ITCZ continues from 04N14W to 03N30W
02N38W and 01N42W. Convective precipitation: widely scattered
moderate to isolated strong from 04N southward between 32W and
45W. isolated moderate elsewhere from 10N southward from 60W
eastward, mostly from 06N southward between 10W and 32W.

One area of high level clouds covers the Atlantic Ocean from 17N
southward, and those clouds are moving eastward. Other high level
clouds are within 210 nm on either side of the line 21N17W 17N29W
10N43W, and those clouds are moving northeastward.

...DISCUSSION...

...THE GULF OF MEXICO...

Upper level NW wind flow spans the entire Gulf of Mexico. The cold
front from 24 hours ago already has cleared the area completely.
Middle level and high level clouds are from 25N northward.
Comparatively drier air in subsidence is apparent in water vapor
imagery from 25N southward.

Surface anticyclonic wind flow covers the Gulf of Mexico. A 1026
mb high pressure center is near 31N88W in SW Alabama.

Low level and middle level clouds cover the area from 90W
westward.

Gale-force winds are blowing in the Gulf of Tehuantepec on the
eastern Pacific Ocean side of southern Mexico. Please read the
Eastern Pacific Ocean HIGH SEAS FORECAST...MIAHSFEP2/FZPN03
KNHC...and the Eastern Pacific Ocean TROPICAL WEATHER
DISCUSSION...MIATWDEP/AXPZ20 KNHC...for more details.

...LOW LEVEL CLOUD CEILINGS 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: KVOA.

LOW LEVEL CLOUD CEILINGS AND WEATHER...FOR THE COASTAL PLAINS OF
THE U.S.A. FROM THE DEEP SOUTH OF TEXAS TO FLORIDA...

from TEXAS to FLORIDA: VFR.

...THE CARIBBEAN SEA...

Middle level NE wind flow moves from Hispaniola, toward Central
America, from Honduras to Panama.

Upper level NW wind flow is moving from Cuba to Hispaniola, and
beyond the SE corner of the Caribbean Sea. Comparatively drier
air in subsidence is apparent in water vapor imagery across the
entire area.

Scattered to broken low level clouds and possible rainshowers are
within 90 nm to 120 nm on either side of the line that runs from
19N75W, to 15N80W, to the coastal border of Costa Rica and Panama.

24-HOUR rainfall totals in inches for the period ending at
31/0000 UTC...according to the PAN AMERICAN TEMPERATURE AND
PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...are 0.01 in
Guadeloupe.

...HISPANIOLA...

Upper level W-to-NW wind flow is moving on top of middle level
anticyclonic wind flow, across Hispaniola. Comparatively drier
air in subsidence is apparent in water vapor imagery, across the
entire area. Convective precipitation: rainshowers are possible
inland, and in the coastal waters, in areas of scattered to broken
low level clouds.

SURFACE OBSERVATIONS...for Port-au-Prince in Haiti: MVFR. drizzle.
for the DOMINICAN REPUBLIC: Barahona: VFR/no ceiling. few
cumulonimbus clouds. Santo Domingo/La Romana: VFR/no ceiling. few
cumulonimbus clouds in each location. Punta Cana: VFR/no ceiling.
Santiago: VFR/no ceiling. few cumulonimbus clouds. Puerto Plata:
VFR/no ceiling.

The GFS MODEL forecast for 250 MB shows that a Colombia-to-Yucatan
Peninsula ridge will bring NW wind flow across the area during
the next 48 hours. The GFS MODEL forecast for 500 MB shows that
an E-to-W oriented ridge will bring anticyclonic wind flow across
the area during the first 24 hours of the 48-hour forecast. Day
two will consist of N-to-NE wind flow. The GFS MODEL forecast for
700 mb shows that NE-to-E wind flow will move across Hispaniola,
during the next 48 hours, with an Atlantic Ocean anticyclonic
circulation center and a ridge.

...THE ATLANTIC OCEAN...

A deep layer trough, that was moving through the eastern U.S.A.
during the last 24 hours, now is the western Atlantic Ocean,
passing through 34N67W to 30N69W and 29N71W. The trough supports
the cold front that moved through the Gulf of Mexico during the
last 24 hours. The front now passes through 32N63W to 25N67W, to
the SE Bahamas. The cold front is dissipating from the SE Bahamas,
across NW Cuba, to the NE corner of the Yucatan Peninsula.
Convective precipitation: isolated moderate from 25N northward
between 55W and 63W. Other multilayered clouds and possible
rainshowers are from 24N northward from 54W westward. Scattered to
broken low level clouds and possible rainshowers are in the
northwestern corner of the Caribbean Sea, to the NW of the line
that runs from the central coast of Cuba, to the central coast of
Honduras. Low-level to middle level clouds, that are in the area
of a surface-to-low level trough, are within 75 nm on either side
of 25N65W 20N70W, to Hispaniola. Rainshowers are possible in this
band/line of clouds.

An upper level trough passes through 32N47W to 27N45W to 21N46W
and 15N48W. High level clouds cover the Atlantic Ocean from 19N to
32N between 38W and 46W.

An upper level trough passes through 32N23W to 23N31W 16N44W
15N53W and 15N60W. A surface trough extends from a 1016 mb low
pressure center that is near 32N24W, to 30N22W and 28N23W. No
significant deep convective precipitation is apparent.

Surface anticyclonic wind flow covers the Atlantic Ocean from 15N
northward between 28W and 60W. A 1027 mb high pressure center is
near 31N45W.

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

$$
MT
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