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Atlantic Tropical Weather Discussion

AXNT20 KNHC 161735

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 UTC Sat Oct 16 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 
1700 UTC.


Atlantic Gale Warning: A 1001 mb low pressure center is located 
near 35N38W. A cold front extends from the low to 26N50W, then a 
trough continues from that point to 23N63W. A tight pressure
gradient between the front and a surface ridge to the east is
supporting minimal gale force winds east of the front. Seas over
the gale area are currently reaching near 15 ft. The low pressure
area will continue to shift further NE away from the area, with
the gales moving north of the area by tonight. 

Gulf of Mexico Gale Warning: A cold front extends over the NW 
Gulf of Mexico from 30N88W to 23N98W. The front will continue to 
spread southeast across the Gulf waters this weekend. Fresh to 
strong winds are currently west of the front. Winds will 
increase to gale force this afternoon over the waters off 
Tampico, Mexico. These winds will spread southward, extending 
off the coast of Veracruz, Mexico on Sun. Seas will peak near 13 
ft off Veracruz, Mexico by Sun afternoon.

Please read the latest High Seas Forecast issued by the National
Hurricane Center at website for more details
on both warnings.


The axis of a tropical wave is near 36W south of 18N, moving W at
10 to 15 kt. This mornings scatterometer data depicted a decent 
curvature with this wave. Scattered moderate convection is from 
01N to 10N between 30W and 42W. 

The axis of a tropical wave is near 49W south of 19N, moving W 
at 10 to 15 kt. No significant convection is related to this 
wave at this time. 

The axis of a tropical wave is near 70W south of 20N, moving W at
10 to 15 kt. Scattered moderate to strong convection is 
developing over the southern portion of the wave currently 
extending across western Venezuela/eastern Colombia.

The axis of a tropical wave is near 83W south of 19N, moving W at
10 to 15 kt. Scattered moderate convection is noted S of 13N
between 75W and 85W.


The monsoon trough extends from the coast of Africa near 13N17W 
to 06N23W. The ITCZ continues from 06N23W to 06N34W. It resumes 
from 05N38W to 06N47W, and then from 06N52W to 07N58W. Aside from
convection mentioned in the Tropical Waves section, scattered
moderate convection is noted from 01N to 13N between 18W and 


Refer to the Special Features for information on the Gale Warning
in effect for the SW Gulf of Mexico.

Aside front the cold front described above, a pre-frontal trough 
extends from 30N83W to 26N87W. Scattered showers are noted S
of 26N and W of 90W. Weak high pressure prevails over the 
remainder of the basin. Light to gentle winds prevail SE of the 
front with seas of 1-3 ft. 

For the forecast, the cold front will continue moving SE across 
the basin. Winds will gradually veer from the E Mon through 
Tue as the front becomes aligned W to E along 23N and dissipates.


Please refer to the section above for details on the tropical 
waves moving across the basin.

A weak pressure pattern prevails across the Caribbean waters.
Gentle to moderate winds and seas of 3-4 ft are over the 
central and eastern Caribbean waters south of 14N. Light to 
gentle winds and seas of 1-3 ft prevail across the remainder of 
the Caribbean waters.  

For the forecast, a very weak pressure gradient between the W 
Atlc and the Caribbean basin will lead to tranquil marine 
conditions through early Mon. A cold front will enter the NW 
Atlc over the weekend and move SE. High pres building in the 
wake of the front will bring a return to moderate trade winds to 
the Caribbean Mon night.


Please refer to the Special Features section above for details on
the Gale Warning and tropical waves currently across the basin.

A 1011 mb surface low is centered near 30N66W. A surface trough 
extends from the low to 25N67W. No significant convection is 
related to these features at this time. To the east, scattered 
moderate convection prevails N of 18N between 37W-59W related 
to the gale front/trough. Aside from the gale conditions east
of the front/trough, gentle to moderate winds and seas of 4-6 ft 
are found N of 20N and E of 60W. W of 60W, light to gentle winds 
prevail. Seas W of 60W are in the 3-5 ft range over the open 
waters, and 1-3 ft west of the Bahamas. Over the tropical waters 
south of 20N, moderate to fresh winds and seas of 5-7 ft are 

The Cumbre Vieja volcano, on the island of La Palma in the 
Canary Islands, has been erupting since 19 September 2021. 
Low ash concentrations moving NW. Marine and aviation interests 
should monitor this ongoing situation by reading the Volcanic 
Ash Advisory issued by Meteo-France at

For the forecast W of 65W, weak pres pattern prevails today 
across the W Atlantic to the SW of Bermuda. A cold front will 
move southeastward off the SE U.S. coast Sat night and all of 
across Florida by Sun night, reaching from Bermuda to the 
Florida Keys by Mon morning. Expect fresh to strong N to NE 
winds behind the front through Mon morning.