AXNT20 KNHC 072233
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0005 UTC Wed Dec 8 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
East Atlantic Gale Warning: A strengthening Azores high will
tighten the pressure gradient off the coast of Morocco,
generating localized N-NE gales and 12-15 ft seas by Thursday
morning in the marine zone Agadir. Please ready the latest High
Seas Forecast issued by Meteo-France at website
The monsoon trough is over the African continent. The ITCZ
extends from the coast of Sierra Leone near 08N13W to 04N30W to
the coast of South America near 06N55W. Scattered moderate
convection is noted from 02N-06N between 28W- 38W.
GULF OF MEXICO...
A stationary front is along the northern Gulf of Mexico from
29N84W to near 22N98W. A surface trough extends from the Bay of
Campeche to the southeast Gulf of Mexico. High pressure of 1019
mb near Tampa Bay extends surface ridging over the central Gulf
generating mainly gentle anticyclonic winds in the eastern and
central Gulf with seas of 1-2 ft. Moderate northerly winds are
present northwest of the stationary front along the coast of Texas
and northeastern Mexico, where seas are 3-4 ft.
For the forecast, the stationary front will retreat inland by
tonight. A ridge will build westward across the basin, with a
high pressure cell remaining over the eastern Gulf. Moderate to
fresh southerly return flow will set-up across the western and
central Gulf on Fri and Sat, ahead of a strong cold front forecast
to push off the Texas coast by Sat morning. Increasing winds and
building seas are expected in the wake of the front. Gale
conditions are possible behind the front for the area of Tampico
and Veracruz beginning Sat afternoon.
Strong NE to E winds continue off the coast of Colombia, along
with 8 to 10 ft seas. Fresh trades dominate the rest of the
central and eastern Caribbean, with seas of 6 to 8 ft. In the NW
Caribbean, gentle to moderate winds and seas of 3 to 5 ft prevail.
For the forecast, high pressure N of the area will extend a ridge
across the northern Caribbean Sea and combined with the Colombian
low will support fresh to strong trade winds over the south-
central basin and in the Gulf of Venezuela through the weekend.
Moderate to fresh trades will prevail elsewhere except in the NW
Caribbean where mainly gentle to moderate winds are expected
before the weekend. By Thu night into Sun night, as high pressure
strengthens over the western Atlantic, expect fresh to locally
strong NE winds in the Windward Passage, the lee of Cuba and, S of
The combination of a surface trough extending across the
northwest Bahamas to 30N75W and upper-level divergence is
generating scattered showers and thunderstorms east of the
trough axis between 70W and 75W and from 25N to 31N. Farther
east, a second trough is noted from 30N58W to 21N57W.Between the
two troughs, surface ridging is keeping winds gentle. Fresh to
locally strong NE to E winds prevail across the central tropical
Atlantic north of the ITCZ between 30W and 50W. Seas in this area
are 7-10 ft. Between 60W and the Bahamas seas are 3-5 ft. An
upper-level low W of the Canary Islands is generating scattered
showers and isolated thunderstorms north of 25N and east of 23W.
For the forecast west of 65W, a ridge will prevail along 26N-27N
through the weekend. Moderate to fresh NE to E winds are expected
along the southern periphery of the ridge, especially south of
22N, including the waters just N of Hispaniola and approaches to
the Windward Passage. A stationary front over the far NW waters is
forecast to lift northward tonight. The next front will move over
the northern forecast waters Thu and Fri while dissipating.
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 W of the