Skip Navigation Links
NOAA NOAA United States Department of Commerce

Atlantic Tropical Weather Discussion



117 
AXNT20 KNHC 291714
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 UTC Mon Nov 29 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 
1710 UTC.

...MONSOON TROUGH/ITCZ...

The monsoon trough extends from the coastal border of Sierra Leone
and Guinea near 09N13W and continues to 07N19W. The ITCZ then 
continues from 07N19W to 03N33W. A surface trough is along 37W
extending from 01N to 08N. Scattered moderate to isolated strong
convection is observed from 03N to 08N and between 30W and 45W.
Also, scattered moderate convection is found near the monsoon 
trough and the coast of Africa, mainly east of 18W.

GULF OF MEXICO...

As of 1500 UTC, a cold front extends from the Bahamas through the
Florida Straits where it transitions into a dissipating cold front
near 23N83W. The dissipating boundary continues into the Bay of
Campeche. Behind this boundary, strong high pressure is building
through the Gulf of Mexico resulting in fairly tranquil weather
conditions. Recent scatterometer satellite data and surface
observations show fresh to occasionally strong N-NE winds behind 
the frontal boundary, mainly South of 27N. The strongest winds are
found offshore Veracruz. Seas of 6-9 ft are present behind the 
front, with the highest seas occurring offshore Veracruz. 
Elsewhere, moderate or weaker winds and seas of 3-6 ft prevail.

For the forecast, the aforementioned front will move southeast 
and dissipate through late today. High pressure will build across 
the Gulf in the wake of the front. As high pressure moves 
eastward, southerly return flow will set-up across the NW Gulf by 
mid-week.

CARIBBEAN SEA...

Trade wind convergence along with divergent flow aloft east of a
weak mid/upper level trough over Nicaragua are together supporting
a large area of showers and isolated thunderstorms, mainly within
200 nm of Nicaragua, Costa Rica and Panama. Satellite derived 
winds and surface observations indicate fresh to locally strong 
trades in the south-central and SW Caribbean Sea, with the 
strongest winds occurring within 60 nm of the Nicaraguan coast. 
Seas of 4-7 ft are also found in the region. Clear skies and light
winds over western Cuba allowed for colder than normal 
temperatures, with some areas reporting temperatures below 50F. 
Elsewhere, fairly tranquil weather conditions, moderate or weaker 
trades and seas of 1-4 ft are prevalent.

For the forecast, moderate to fresh NE to E winds will persist 
over all but the NW Caribbean through mid week, with strong winds 
pulsing off Colombia, mainly at night. High pressure building 
north of the area will slightly enhance trade winds across the 
Caribbean later in the week. Meanwhile, moderate N to NE swell 
will continue across the Atlantic waters east of 70W and through 
the NE Caribbean passages through tonight

ATLANTIC OCEAN...

A cold front extends from a low pressure center near 36N71W into
the Florida Straits, entering the tropical Atlantic near 31N72W. A
pre-frontal trough extends from 30N70W to 23N73W. Scattered
moderate convection is found east of the frontal boundary to 65W
and north of 27N. Recent scatterometer satellite data depict fresh
to strong westerly winds behind the frontal boundary, with the
strongest winds occurring north of 29N. Seas of 5-8 ft are found
behind the frontal boundary.

Over the Central Atlantic, a surface trough extends from 28N40W to
23N43W and a few showers are noted near the northern end of the
trough. A strong 1038 mb high pressure center near the Azores and
lower pressures over western Africa allow for a moderate pressure
gradient, resulting in a large area of fresh to strong 
anticyclonic winds east of 40W and north of 05N. The strongest
winds are occurring east of 30W and north of 14N, including the
waters surrounding the Canary Islands. Seas of 8-11 ft are 
present east of 45W, with the highest seas occurring north of the
Cabo Verde Islands. Elsewhere, fairly tranquil weather 
conditions, moderate or weaker winds and seas of 5-8 ft prevail.

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/.

For the forecast west of 65W, the previously-mentioned cold front
will move quickly SE across the forecast waters, and reach from 
31N65W to eastern Cuba by tonight. High pressure will settle 
across the forecast area in the wake of the front, and dominate 
the SW N Atlantic through Fri.

$$
FLYNN/DELGADO