[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 262208
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0005 UTC Wed Oct 27 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
2120 UTC.

...TROPICAL WAVES...

An Atlantic tropical wave is along 28W from 18N southward, moving
W at 10-15 kt. Scattered moderate and isolated strong convection
is evident east of the wave axis from 03N to 16.5N to the
African coast.

A Caribbean tropical wave is analyzed along 73W south of 16N,
moving W at 15-20 kt. Although the wave shows up well in total
precipitable water imagery, no significant convective activity is
noted over waters near the wave at this time.

...MONSOON TROUGH/ITCZ...

The monsoon trough extends off the coast of Guinea-Bissau near
12N16W to 12.5N27W. The ITCZ extends from 07N30W to 08.5N61W. In
addition to the convection described in the Tropical Waves
section, scattered moderate to strong convection is occurring on
either side of the ITCZ, from 05N to 10N between 27W and 57W.

GULF OF MEXICO...

A cold front is across the northern Gulf from near Tampa Bay
Florida to near Lake Charles Louisiana. Moderate NW to N winds
are north of the front over the far northeast Gulf of Mexico,
where seas are 2 to 3 ft. No significant precipitation is observed
near the front. Farther south, a surface trough extends from
24N88W to 19N93W, west of the Yucatan Peninsula. Moderate SE
winds and 2 to 3 ft seas are occurring in the NW Gulf west of 94W.
Gentle winds and 1 to 2 ft seas prevail elsewhere.

Fresh to strong southerly winds will develop across the NW Gulf
tonight into Wed ahead of a cold front expected to push off the
Texas coast by midday Wed. The front will reach from Tallahassee
to 25N88W to 19N95W by Thu morning, and from Ft Myers, Florida to
Cancun, Mexico Thu night. Strong to minimal gale force winds are
expected ahead of and behind the front. Seas will build to 13 ft
in the wake of the front, especially over the north-central and NE
Gulf. A squall line containing strong to severe thunderstorms
with very strong wind gusts is expected to accompany the cold
front as it moves from west to east Wed afternoon through Thu
morning. The strongest thunderstorms should occur over the
northwest and north-central Gulf with the line, Wed afternoon
through Wed night. Frequent gusts to gale force are expected over
the north-central and NE Gulf Wed night through Fri before quickly
diminishing early Sat.

CARIBBEAN SEA...

Mid to upper-level ridging prevails over the western two-thirds of
the Caribbean Sea, leading to subsidence and mostly dry
conditions, other than a few isolated showers with the typical
trade wind cumulus clouds. Although an upper-level trough extends
from the central Atlantic to the eastern Caribbean Sea, relatively
dry air is limiting shower activity there as well. A 1015 mb
surface high pressure is analyzed over eastern Cuba near 20.5N78W.
As a result of this high pressure, morning ASCAT data showed
light to gentle wind speeds over the NW Caribbean, except for the
Gulf of Honduras, where moderate winds are noted. Seas are 1 to 3
ft in the NW Caribbean, except up to 4 ft in the Gulf of Honduras.
ASCAT data also showed fresh trades over the southeast and south-
central Caribbean, mainly south of 15N and east of 77W, where seas
are currently in the 5 to 7 ft range. Gentle to moderate winds
prevail elsewhere, with 2 to 4 ft seas.

The Azores high will continue to extend a ridge SW to the NE
Caribbean and support the continuation of moderate to fresh winds
across the eastern half of the basin with slightly higher winds in
the Gulf of Venezuela through Thu. A cold front will enter the NW
Caribbean Thu night and reach from western Cuba to the Gulf of
Honduras early in the afternoon on Fri. The front will reach from
eastern Cuba to the coast of Nicaragua on Sat where it will stall
before dissipating Sun. Moderate to fresh northerly winds will
follow the front.

ATLANTIC OCEAN...

West of 60W: A cold front enters the area near 31N74W and extends
to Cape Canaveral Florida and into the eastern Gulf of Mexico.
Another cold front extends from the central Atlc to 31N70W, then
continues as a surface trough to the NW Bahamas near 25.5N77W. An
upper-level trough axis is also over this general area. Upper-
level diffluence to the east of the upper-trough is enhancing
scattered moderate and isolated strong convection north of 25N
between 61W-71W. Isolated tstorms are also along the cold front
near 30N-31N and 69W-71W. Strong to near-gale force S to SW winds
are noted within 300 nm east of eastern front/surface trough,
mainly north of 29.5N. Seas of 8 to 11 ft prevail north of 28.5N
between 62W-72W. 6 to 8 ft seas are elsewhere north of 27.5N
between 62W-80W. Mainly moderate W wind prevail through the
northern Bahamas. A weak surface ridge is oriented over the
Greater Antilles, where gentle wind speeds are occurring. East of
the Bahamas and south of 26N, seas are 3 to 5 ft.

East of 60W: A weak ridge axis extends from 1024 mb high pressure
near 35N21W to near 21N50W, while another ridge extends from
30N57W to 20N66W. This pattern is supporting moderate to fresh
trade winds south of 15N, and gentle winds in the subtropical
latitudes north of 17N. Seas are 6 to 9 ft over the tropical
Atlantic in the area of moderate to fresh trade winds, with
small to moderate N swell. Seas are 4 to 6 ft elsewhere, except 5
to 7 ft east of 30W.

The Cumbre Vieja volcano, on the island of La Palma in the Canary
Islands, has been erupting since 19 September 2021. Ash cloud
slowly drifting SW. Higher concentration over volcano and western
vicinity. 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, fresh to strong winds will push
eastward across the northern forecast waters, mainly N of 27N,
through Wed as the two fronts merge and move eastward. The next
cold front is expected to sweep across the region Thu night
through Fri night producing another round of fresh to strong winds
north of the Bahamas. Scattered showers and tstorms will likely
accompany this front.

$$
Stripling
This weather bulletin was brought to you by:
www.nashvilleweather.net