[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 180600
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0605 UTC Sat Dec 18 2021

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 31N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 0000 UTC surface analysis and satellite imagery through
0540 UTC.

...SPECIAL FEATURES...

Gale-force winds are forecast by the METEO-FRANCE, for the area
AGADIR. The gale-force winds will last from 03z today, until 18z
later in the day today. Please, refer to the website:
http://www.gmdss.org/bulletins/METAREA2.HIGH_SEAS_WARNING.1915.17
19153323576.html, for more details.

...MONSOON TROUGH/ITCZ...

The monsoon trough passes through the Prime Meridian at 06N, to
05N10W, to 04N12W, and to 04N17W.  The ITCZ continues from
04N17W, to 05N22W, and 06N26W. A surface trough is along 07N35W
05N37W 03N38W. Precipitation: scattered to numerous strong is
within 135 nm to the north of the ITCZ between 27W and 31W.
Widely scattered moderate to isolated strong is elsewhere from
09N southward between 25W and 37W. Isolated moderate is from the
monsoon trough/ITCZ southward from 25W eastward.

GULF OF MEXICO...

A surface ridge passes through NE Florida, to the Florida
Panhandle, and beyond SW Louisiana.

The GFS model for 250 mb shows that a trough passes through SE
Louisiana, to the Yucatan Peninsula, to SW Honduras.
Precipitation: widely scattered moderate to isolated strong is
between 84W and 88W.

Moderate to fresh winds prevail. The sea heights range from 3
feet to 5 feet.

High pressure north of the Gulf will prevail through Sat,
supporting moderate to locally fresh SE to S winds. A cold front
is forecast to enter the basin Sat night. Strong N to NE winds
and building seas will prevail west of the front on Sun. By Mon,
low pressure should develop along the cold front in the central
Gulf and steadily progress east-northeastward, pulling the front
across the Gulf by Tue. Winds and seas across the Gulf should
subside slowly on Wed.

CARIBBEAN SEA...

The GFS model for 250 mb shows that a trough passes through SE
Louisiana, to the Yucatan Peninsula, to SW Honduras.
Precipitation: widely scattered moderate to isolated strong is
in the coastal plains and in the coastal waters of Central
America from 11N northward.

Upper level anticyclonic wind flow spans the rest of the
Caribbean Sea, from 80W eastward.

The monsoon trough passes through 10N, from Colombia beyond
Costa Rica, into the eastern Pacific Ocean. Precipitation:
isolated moderate is within 60 nm to 90 nm to the north of the
monsoon trough, in the SW corner of the Caribbean Sea.

Isolated moderate rainshowers are associated with broken to
overcast low level clouds, that are moving with the low level
wind flow, in the remainder of the Caribbean Sea.

Near gale-force winds are within 300 nm to the north and
northwest of the coast of Colombia. Strong winds are within 430
nm to the north and northwest of the coast of Colombia. Strong
winds are in the Caribbean Sea and in the Atlantic Ocean: from
10N to 26N between 45W and 69W. Fresh-to-strong winds are from
27N southward between 73W and the central coastal sections of
Cuba. The sea heights range from 8 feet to 12 feet, from the
Greater Antilles southward between 63W and 80W. The sea heights
range from 6 feet to 7 feet, elsewhere, to the east of 63W. The
sea heights range from 3 feet to 5 feet, elsewhere, to the
northwest of the large area of sea heights that are 8 feet or
higher.

High pressure, building south through the Atlantic Ocean, will
support fresh to strong trades in the central and eastern
Caribbean Sea, and in the tropical N Atlantic Ocean, this
weekend. The high will move east for the start of next week,
leading to weaker trades. Large N to NE swell, reaching the
tropical N Atlantic Ocean, and the Mona Passage and the Anegada
Passage tonight, will continue through Mon.

ATLANTIC OCEAN...

A cold front passes through 31N25W, to 25N30W, 21N40w, and
20N44W. A shear line continues westward, along 19N/20N, between
44W and 64W. Precipitation: widely scattered moderate to
isolated strong is within 120 nm to the east of the cold front
from 27N northward. Isolated moderate is within 240 nm to the
east and southeast of the cold front from 24N to 27N. Broken to
overcast mostly high level clouds are within 800 nm to the
southeast of the cold front from 36W eastward, and from 12N to
18N between 50W and the eastern Caribbean Sea islands. Strong
winds are within 180 nm to the north of the cold front between
37W and 43W.

A surface ridge is along 26N42W, to a 1027 mb high pressure
center that is near 31N63W, beyond 32N75W.

The sea heights range from 11 feet to 15 feet from the cold
front northward, from 50W eastward; and from 17N to 24N between
50W and 60W. The sea heights range from 6 feet to 9 feet from 65W
westward. The sea heights range from 7 feet to 8 feet from 12N to
the cold front between 40W and 50W. The sea heights range from 3
feet to 5 feet in the remainder of the area from 40W eastward, and
to the east and southeast of the cold front.

Near gale-force winds are: from 20N to 22N between 47W and 52W,
and from 13N to 17N between 58W and 67W. Strong winds are: from
10N to 26N between 45W and 69W. Fresh-to-strong winds are from
27N southward between 73W and the central coastal sections of
Cuba.

High pressure centered NE of the area is supporting gentle to
moderate winds N of 25N, and fresh to strong winds to the south,
where the pressure gradient between the high and lower pressure
in the Caribbean is tighter. These higher winds will persist
through the weekend, until the high moves E of the area for the
start of next week and a cold front moves off the SE U.S. coast. Tue
into Wed: low pressure developing along or just off the coast of the
Carolinas will lead to increasing winds N of 28N, with strong winds
likely in this region. Large N swell impacting the Atlantic zone
from 19N-22N between 55W-65W will diminish on Sun.

$$
mt/sk
This weather bulletin was brought to you by:
www.nashvilleweather.net