AXNT20 KNHC 011645
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 UTC Wed Dec 1 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
The monsoon trough axis enters the Atlantic Ocean through the
coast of Guinea and extends to near 10N16W. The ITCZ continues
from 10N16W to 05N30W to 04N50W. Scattered moderate convection is
noted from 01N to 16N between the African coast and 40W.
GULF OF MEXICO...
A trough analyzed in the Bay of Campeche from 24N96W to 19N93W is
producing cloudiness with possible embedded showers. Moderate SE
winds are noted in scatterometer data east of the trough. A trough
in the northwest Caribbean extends into the Yucatan Channel and
southeast Gulf. The remainder of the basin is dominated by surface
ridging anchored by a 1025 mb high pressure over southwest
Georgia. Seas of 1 to 3 ft and light to gentle winds prevail
across most of the basin.
For the forecast, the high pressure building across the northern
Gulf will dominate the basin into the weekend. This high pressure
will gradually move eastward, returning the east to southeast flow
across the northwest Gulf by the end of the week.
A trough analyzed just east of the Yucatan peninsula from 21N86W
to 17N88W is producing some cloudiness and weak showers.
Scattered moderate to isolated strong convection is noted in the
far southwest Caribbean south of 13N near the northern Panama,
Costa Rica, and Nicaragua coastlines associated with the east
Pacific monsoon trough. Farther east, a westward moving trough
extends roughly along 66W from 18N to 11N. Scattered moderate
convection is active along the trough south of 16N. Fresh to
locally strong winds are observed in a recent scatterometer pass
on either side of the trough.
Fresh to locally strong winds are likely occurring off Colombia,
with moderate to fresh NE to E winds elsewhere over the northern
and central Caribbean, to include in the lee of Cuba, the Windward
Passage, and off the southern coast of Hispaniola. Seas are 2 to
4 ft across the northwest Caribbean and 5 to 6 ft elsewhere, with
the exception of 7 to 8 ft off the coast of Colombia.
For the forecast, high pressure north of the area will maintain
generally moderate to fresh NE to E winds across the Caribbean
into the weekend, with fresh to strong winds pulsing off Colombia
and the Gulf of Venezuela, mainly at night. Moderate to fresh NE
winds are also possible over the Windward Passage and Mona
A cold front extends from 31N55W to 27N61W then becomes
stationary to 24N69W. The front disrupts the subtropical ridge
between strong 1038 mb high pressure near the Azores Islands and
1025 mb high pressure between the Carolinas and Bermuda. Scattered
moderate showers and thunderstorms are observed along and within
180 nm east of the front north of 28N. Recent scatterometer and
altimeter passes observed fresh to strong winds and 5 to 6 ft seas
just east of the front, north of 28N. The altimeter satellite
pass from this morning confirmed seas reaching 8 ft in NE swell in
the vicinity of 30N65W. A strong pressure gradient between the
Azores high and lower pressure near the ITCZ is causing fresh to
strong NE to E trade winds and 8 to 11 ft seas over most of the
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
For the forecast west of 65W, a weak trough will move off
northeast Florida tonight, then lift northeast of the area. A
ridge will build along 27N/28N through Fri, supporting moderate to
fresh trade winds south of 22N by late Fri.