[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 241155
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
655 AM EST Sun Dec 24 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.

...Gale Warning in the Caribbean Sea...

Please read the latest NHC High Seas Forecast under AWIPS/WMO
headers MIAHSFAT2/FZNT02 KNHC for more details. NE gale-force
winds, and sea heights ranging from 10 feet to 13 feet, are being
experienced from 10.5N to 13.5N between 72W and 75W. Expect these
conditions for this morning.

...ITCZ/MONSOON TROUGH...

The monsoon trough passes through the Prime Meridian along 04N,
to 02N10W and 04N18W. The ITCZ continues from 04N18W to 05N23W
and 02N41W. Precipitation: scattered moderate to strong from 03N
to 06N between 28W and 43W. isolated moderate to locally strong
elsewhere from 10N southward from 60W eastward.

...DISCUSSION...

...THE GULF OF MEXICO...

Upper level SW wind flow and broken-to-overcast high level clouds
cover the NW half of the Gulf of Mexico. Anticyclonic wind flow
and comparatively drier air in subsidence in water vapor imagery
cover the SE half of the area.

A cold front passes through the Florida Panhandle, into the
central Gulf of Mexico, into the SW corner of the area. The part
of the front that is to the west of 90W is becoming stationary.
The rest of the front is moving ESE slowly. A few of the oil
platform observations show some low clouds, still, in the wake of
the cold front. Low clouds and possible rainshowers cover inland
areas from Guatemala to the Isthmus of Tehuantepec. Rainshowers
are possible also in the SW corner of the Gulf of Mexico from 20N
southward. The wind forecast, for the part of the Gulf of Mexico
that is from 23N southward to the west of the front, consists of
NW-to-N winds 20 to 30 knots and sea heights from 8 feet to 9
feet. Surface high pressure has become established from Texas to
the Isthmus of Tehuantepec of southern Mexico. A 1025 mb high
pressure center is near 22N98W in Mexico.

A surface ridge extends from 27N73W in the Atlantic Ocean, across
the Bahamas, into the Gulf of Mexico near 23N87W.

...THE CARIBBEAN SEA...

Upper level cyclonic wind flow covers the area that is from 70W
eastward, with the 26N51W 17N60W 15N65W Atlantic Ocean-to-
eastern Caribbean Sea trough, that has remained in the area during
the last day or two. A second upper level trough extends from the
Windward Passage to Honduras. Isolated moderate rainshowers are in
the Caribbean Sea from 12N to 14N between 82W and 85W, mostly
moving into Nicaragua. Rainshowers are possible, elsewhere, in
areas of broken low level clouds that are spread across the rest
of the Caribbean Sea.

24-hour rainfall totals in inches, for the period that ended at
24/0000 UTC, according to the PAN AMERICAN TEMPERATURE AND
PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...are: 0.12 in in
Guadeloupe, and 0.01 in Curacao.

...HISPANIOLA...

Upper level NE wind flow, and comparatively drier air in
subsidence in water vapor imagery, cover Hispaniola.

SURFACE OBSERVATIONS...HAITI, in Port-au-Prince: VFR. in the
DOMINICAN REPUBLIC: Santiago: MVFR. mist and low visibilities.
Puerto Plata: MVFR. ceiling 1800 feet. VFR...elsewhere. Low clouds
are moving from the coastal waters of Hispaniola, onshore, and
then across land.

The GFS MODEL forecast for 250 mb shows that day one will consist
of a trough in the eastern half of the island and a ridge in the
western half of the island. The trough will shift to the
northern half of the island, and a ridge will cover the southern
half of the island. A ridge finally covers the entire island by
the end of day one. Expect NW wind flow everywhere during day
two. The GFS MODEL forecast for 500 mb shows that NE wind flow
will move across the area during the next 2 days. An anticyclonic
circulation center will be across Cuba. The GFS MODEL forecast
for 700 mb shows that the first half of day one will consist of
E-to-SE wind flow, and the second half of day one will consist of
NE wind flow. Day two will consist of NE wind flow.

...THE ATLANTIC OCEAN...

An upper level trough passes through 32N40W to 27N50W to 20N58W
and 14N67W in the eastern Caribbean Sea. A surface trough is
along 55W/56W from 28N to 32N. A second surface trough is along
67W/68W from 25N to 31N. Precipitation: isolated moderate from
10N to 24N between 40W and 60W. rainshowers are possible from 22N
to 30N between 60W and 80W.

Surface anticyclonic wind flow covers the Atlantic Ocean from 15N
northward between Africa and 50W.

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

$$
MT
This weather bulletin was brought to you by:
www.nashvilleweather.net