[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 071059
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1205 UTC Thu Oct 7 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 0600 UTC surface analysis and satellite imagery through
0930 UTC.

...TROPICAL WAVES...

An Atlantic Ocean tropical wave is along 28W, from 16N southward,
moving W at 10 to 15 knots. A large middle to upper level cyclone
centered over the Cabo Verde Islands is strongly shearing this
wave. Overcast multilayered clouds with scattered moderate
convection extends from the eastern Cabo Verde from 24W eastward
to 20W. Scattered to numerous moderate to strong convection is
seen on both sides of the ITCZ S of 09N S of the wave described
below.

An Atlantic Ocean tropical wave is along 55W/56W, from 19N
southward, moving W at 15 to 20 knots. A sharp middle to upper
level trough is just NW of the wave along 59W/60W and N of 14N and
is acting to sustain active convection associated with this wave.
Scattered moderate isolated strong is from 09N to 14N between 51W
and 59W, and S of 11N between 59W and 63W.

A Caribbean Sea tropical wave is along 86W, from 19N southward,
moving W at 10 to 15 knots. High pressure aloft across the NW
Caribbean is providing favorable upper level conditions to sustain
convection. Scattered moderate to strong convection is to the W
and N of the wave from from 15N to 21N between 84W and 90W.
Scattered moderate to numerous strong convection is also along the
monsoon trough across the eastern Pacific Ocean from Costa Rica
to 91W.

...MONSOON TROUGH/ITCZ...

The monsoon trough passes through coastal Gambia near 12.5N17W to
09N18W The ITCZ continues from 09N18W to 06N26W to 11N53W.
Scattered to numerous moderate to strong convection is noted from
02N to 09N between 18W and 31W, within 210 nm NE of the ITCZ
between 31W and 52W.

GULF OF MEXICO...

An upper level cyclone over the upper Mississippi River Valley and
an upper ridge across the NW Caribbean combine to produce strong W
to SW flow aloft across the entire Gulf basin. A weakening
stationary front extends from near Pensacola, FL to the central
Bay of Campeche. Isolated tstorms are seen along the front N of
27.5N, while scattered moderate isolated strong convection is on
either side of the front S of 21.5N.

Weak high pressure NW of the front is driving only gentle to
moderate N to NE wind west of the front, except around 20 kt
acrossthe area near Veracruz, Mexico. Gentle to moderate E to SE
winds prevail E of the front. Seas are generally slight across
the basin, except 4 to 5 ft offshore of Veracruz.

The weakening stationary will meander today before drifting NW
and gradually dissipating through Fri. Weak high pressure to the
NW will support moderate to locally fresh northerly winds over
Veracruz adjacent waters through Fri. High pressure will build
modestly across the basin this weekend into early next week, and
produce fresh return flow across NW portions Sun through Mon.

CARIBBEAN SEA...

A broad upper trough extends from Hispaniola northward across the
Atlantic, while an sharp and narrow upper trough is along 60W to
the N of 10N. A broad area of low to middle level moisture has
converged to the N and E of the tropical wave along 86W, yielding
active convection. Scattered moderate isolated strong convection
is across the SW Caribbean S of 12.5N between coastal Colombia and
coastal Nicaragua. Small widely scattered clusters of moderate
convection are seen elsewhere inside the Caribbean. Fresh to
strong trade wind prevail across most of central portions of the
basin between 68W and 80W, where seas are 7 to 10 ft. Fresh
trades and seas 5 to 6 ft prevail to the E.

Fresh to locally strong trade winds across the majority of
central Caribbean today will reduce coverage to across the south
central Caribbean tonight behind the tropical wave exiting the
western Caribbean. A tropical wave will move across the tropical
Atlantic waters today through early Fri and weaken as it enters
the E Caribbean Fri. A low level disturbance accompanied by strong
winds, seas 8 to 10 ft, and very active weather will enter the
tropical Atlantic waters early Fri and reach the central Lesser
Antilles Fri morning. Strong upper level wind shear across the E
and NE Caribbean during this time is expected to weakening this
system as it moves westward across the E Caribbean Fri through
Sat.

ATLANTIC OCEAN...

1017 mb low pressure is centered along 31N80W, producing moderate
winds and active convection to its N. Isolated clusters of
moderate convection are seen to the E of this features from 30N
northward between 73W and 77W. Gentle SE winds prevail between the
low and 75W, where seas are 4 to 5 ft in NE swell. High pressure
nudging into the SE Bahamas underneath the low is producing fresh
to locally strong trade winds across the SE Bahamas, the Windward
Passage and waters of eastern Cuba, where seas are 7-8 ft.

1022 mb high pressure is centered E of Bermuda near 36N51W. A
lingering frontal trough stretches nearly E to W along 27N-28N
across the central Atlantic between 42W and 60W, and is draped to
the N across a surface trough along 62W. Scattered moderate to
strong convection is seen within 90 nm either side of the frontal
trough. Moderate to fresh trade winds prevail S of 22N across the
tropical Atlantic, where seas are 7-10 ft in fading N swell.

Active convection is S of 16N accompanying the tropical wave along
55W/56W. To the SE of the wave, a disturbance has developed along
the ITCZ in the form of a surface trough along 49W, moving
westward. Very active convection extends from this trough
southeastward into the deep tropics along 31W, and is described
above. Fresh to strong winds and seas locally 9-10 ft are seen
just to the NE of this trough, in the vicinity of 14N49W.

The Cumbre Vieja volcano, that is on the island of La Palma in
the Canary Islands, has been erupting since 19 September at 1410
UTC. Marine and aviation interests should monitor this on-going
situation, by reading the Volcanic Ash Advisory, that is issued
by Meteo-France, at http://vaac.meteo.fr/volcanoes/la-palma/.

Weak low pres 1017 mb near 30.5N80W will drift northward and
persist offshore of the SE U.S. coast through Sun. Fresh to strong
trade winds across the SE Bahamas and Windward Passage will shift
gradually westward and weaken through Fri morning. Otherwise
moderate trade winds will prevail S of 25N through Sat. The low
level disturbance along 49W will enter the tropical Atlantic
waters early Fri and reach the central Lesser Antilles Fri morning
before weakening as it moves westward across the E Caribbean Fri
through Sat, and encounters strong upper level wind shear. High
pres will build into the region Sun and Mon to produce moderate SE
to S winds E of 75W.

$$
Stripling
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