[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 092354
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0005 UTC Fri Dec 10 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 1800 UTC surface analysis and satellite imagery through
2350 UTC.

...SPECIAL FEATURES...

East Atlantic Gale Warning: A strong high pressure of 1035 mb
persists near the Azores Islands. This system is producing a
tight pressure gradient off the coast of Morocco, generating N-NE
gales in the marine zone of Agadir and the northern part of
Tarfaya. These conditions are forecast to continue through 10/0300
UTC. Expect seas of 10-14 ft within the area of gale force winds.
Please read the latest High Seas Forecast issued by Meteo France
at website http://weather.gmdss.org/II.html for more details.

...MONSOON TROUGH/ITCZ...

The monsoon trough remains inland in Africa. The ITCZ extends
from 07N15W to 05N30W to 01N48W. Scattered moderate convection is
noted from 02N-10N between 24W-42W.

GULF OF MEXICO...

High pressure of 1026 mb centered to the W of Delaware extends a
ridge SW into and across the Gulf of Mexico, which is providing
mainly gentle to moderate return flow and seas to 3 ft. Deep
layered dry air and subsidence by a middle-level high centered at
the gulf is supporting fair weather.

For the forecast, the high pressure ridge will gradually shift
eastward through Sat afternoon in response to a strong cold front
that will move over the NW Gulf by early Sat. Moderate to fresh
southerly return flow will set-up across the western and central
Gulf beginning tonight and through Sat ahead of the strong cold
front. Fresh to strong northerly winds and building seas are
expected in the wake of the front through late Sat night. The
front will weaken as it reaches from central Florida to the SW
Gulf Sun and dissipate by Mon evening. Fresh to strong east winds
will spread westward through the Straits of Florida and to the
eastern Gulf S of 26N Mon through Tue night along with building
seas.

CARIBBEAN SEA...

Except for isolated passing showers in portions of the SW
Caribbean due to shallow moisture, most of the Caribbean enjoys
fair weather due to deep-layer dry air across the region as
indicated by microwave and water vapor layered satellite imagery.
The Azores high continues to extend a ridge across the northern
half of the Caribbean, which is tightening the gradient with the
Colombian low and supporting fresh winds basin-wide E of 82W.
Locally strong winds are along the coast of Colombia and along the
Windward passage. Seas in this region range between 5 to 7 ft,
except 8 ft off Colombia.

For the forecast, the pressure gradient between the ridge across
the northern Caribbean Sea and the Colombian/Panamanian low will
continue to support fresh to strong trades over the south-central
Caribbean and in the Gulf of Venezuela through Fri night. Moderate
to fresh trades will prevail elsewhere. High pressure will begin
to strengthen over the western Atlantic tonight resulting in fresh
to locally strong northeast winds to develop in the Windward
Passage, the lee of Cuba and south of Hispaniola through Tue
night.

ATLANTIC OCEAN...

A cold front extends from 31N64W to 30N67W, where it transitions
to a stationary front that continues along 28N75W to 29N80W.
Moderate NE winds are N of this front. Light to gentle variable
winds are in the remainder SW N Atlantic waters, except at the
entrance of the Windward passage where fresh to strong NE winds
are funneling through the passage. The remainder basin is under
the influence of the Azores high, which extends a ridge S to near
17N. This is resulting in mainly fresh trades between 40W and 65W
with seas of 6 to 8 ft. Fresh to strong NE to E winds are
elsewhere E of 40W and N of 15N with seas to 11 ft.

For the forecast west of 65W, the cold front will become
stationary from near 31N59W to 28N78W on Fri and dissipate over
the weekend. High pressure will build across the region in the
wake of the front, producing moderate to fresh NE to E winds S of
22N, and mainly gentle to moderate winds N of 22N through Sat
night. Another cold front will move off the northeast Florida
coast early on Sun, and reach from near 31N65W to South Florida
by Sun night. This front is forecast to dissipate over the
southeastern waters on Mon. High pressure behind the front will
likely bring fresh to strong northeast to east winds mainly across
the waters south of 27N by Mon night. These conditions are
expected to last through Tue night.

The Cumbre Vieja volcano, on the island of La Palma in the Canary
Islands, has been erupting since 19 September 2021. 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/. The latest advisory
states that low ash concentration is expected near and SW of the
volcano.

$$
Ramos
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