[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 141650
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 UTC Tue Dec 14 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 1200 UTC surface analysis and satellite imagery through
1645 UTC.

...MONSOON TROUGH/ITCZ...

The monsoon trough extends from the coast of Sierra Leone near 07N12W
to 05N17W. The ITCZ continues from 05N17W to 06N35W to the coastal
border of French Guiana and Brazil near 04N50W. Scattered
moderate convection is noted within 150 nm north and 90 nm south
of the ITCZ between 20W and 46W.

GULF OF MEXICO...

High pressure prevails over area with two low pressure troughs in
the Bay of Campeche producing isolated moderate convection.
Moderate to fresh winds prevail over the southeast Gulf with
gentle to moderate winds elsewhere. Seas are 4-6 ft over the
southeast Gulf including the Yucatan Channel, 1-3 ft over the
northeast Gulf, and 3-5 ft elsewhere.

For the forecast, high pressure will prevail across the northern
forecast waters through the week. Fresh east winds will spread
westward through the Straits of Florida and into the eastern Gulf
S of 26N through midweek along with building seas.

CARIBBEAN SEA...

The pressure gradient from high pressure centered over the
southeast U.S. combined with lower pressure over Colombia is
supporting fresh to strong easterly winds over the central
Caribbean including the Windward Passage, south of Hispaniola, and
offshore Colombia. Fresh winds prevail across most of the
remainder of the basin. Seas are generally 5 to 7 ft, with a
recent altimeter pass finding up to 8 ft in the central Colombian
basin. Scattered showers and thunderstorms are noted between 70W-
82W and from 14N-17N as well as along the coasts of Costa Rica
and southern Nicaragua.

For the forecast, fresh to strong trades will continue over the
south-central Caribbean through the week. Moderate to fresh
trades will prevail elsewhere. Strong high pressure will prevail
over the western Atlantic through the forecast period. This will
result in fresh to locally strong northeast to east winds in the
Windward Passage, Mona Passage, the lee of Cuba, and south of
Hispaniola through the week.

ATLANTIC OCEAN...

Scattered moderate convection and fresh NE winds associated with
a low pressure trough near Florida extend 180 nm from the coast.
A cold front extends from 31N51W to 29N56W. Scattered moderate
convection is noted within 60 nm of this boundary north of 30N. A
1028 mb Azores high is centered near 37N28W. The pressure
gradient between this area of high pressure and lower pressure
within the monsoon trough and in the vicinity of the ITCZ is
supporting a large area of fresh to locally strong easterly trade
winds across the Atlantic from 13N to 24N with 8 to 10 ft seas.
North of 24N and west of 35W, gentle to moderate trades prevail
with 4 to 7 ft seas. North of 24N and east of 35W, moderate to
fresh NE winds prevail with 7 to 9 ft seas. South of 13N, moderate
to fresh trades prevail with 7 to 9 ft seas.

The Cumbre Vieja volcano, on the island of La Palma in the Canary
Islands, has been erupting since 19 September 2021. Feeble ash
concentrations are expected near the volcano. Marine and aviation
interests should monitor this ongoing situation by reading the
Volcanic Ash Advisory issued by Meteo-France, at
http://vaac.meteo.fr/volcanoes/la-palma/.

For the forecast west of 65W, high pressure will prevail across
the western Atlantic, supporting moderate to fresh winds over the
forecast waters. High pressure will build southward from the
middle to end of the week resulting in an increase in winds and
seas. This pattern will also increase winds and seas east of 65W
through the week.

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