[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 121040
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1205 UTC Fri Aug 12 2022

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
1020 UTC.

...TROPICAL WAVES...

The axis of a tropical wave is across the central Atlantic along
46/47W from 03N-23N, moving westward at 20 kt. A large envelope
of moist air is seen in Precipitable Water imagery between 39W
and 47W, in association with the tropical wave. A large area of
Saharan Air precedes the wave axis, between 48W and 57W. Scattered
moderate isolated strong convection is noted within 150 nm E of
the wave axis from 09.5N to 15.5N, and from 09N to 12N between 46W
and 50W.

The axis of a tropical wave is along 58W from 20N southward to
the Guyana, moving westward at 15 kt. The portion of the wave
north of 12N is currently enveloped in an area of westward moving
Saharan dust. Scattered moderate convection is noted from 10.5N to
12.5N between 53W and 58W.

The axis of a central Caribbean tropical wave is along 72W from
central Hispaniola southward to western Venezuela, moving
westward at 15 kt. Scattered moderate convection is noted from
15.5N to 18N between 67W and 72W.

...MONSOON TROUGH/ITCZ...

The monsoon trough extends from the coast of Senegal near 14.5N17W
to 12.5N23W to 13.5N37W to 10N57W. Aside from the convection
mentioned in the tropical waves section above, scattered moderate
to strong convection is noted from 08N to 13N between 18W and
23W, while scattered moderate is noted from 07.5N to 11N between
35W and 38W.

GULF OF MEXICO...

A recent low to middle level trough over the NW Gulf of Mexico has
weakened overnight, but still supports a surface trough along the
central Texas coast. Ample low level moisture is seen over the NW
and N central Gulf in Precipitable Water imagery. A reinforcing
middle to upper level trough is sinking southward across the Gulf
Coast states and nearing the coasts, and is supporting persistent
scattered moderate isolated strong convection across the N central
and NE Gulf north of 27N. Scattered moderate to strong convection
is seen within 120 nm of the Mexican coast across the SW Gulf.
Although the coverage and intensity of thunderstorms in the N Gulf
has diminished significantly overnight compared to during the
daytime on Thursday, expect thunderstorms to return to the
northwest Gulf during the daytime today as the trough and moisture
sticks around.

Weak surface high pressure extends from the western Atlantic
westward along 29N to SE Louisiana early this morning. Gentle to
moderate anticyclonic winds prevail across the basin. Buoys are
currently reporting 2 to 3 ft seas across most of the basin, with
peak seas likely 4 ft in the Straits of Florida.

The weak high pressure along 29N to the N central Gulf will sink
southeast late Fri through Tue. This will allow for gentle to
moderate winds over the basin to weaken to light to gentle into
next week. Moderate NE to E winds will pulse to fresh during the
late afternoon and evenings off the NW Yucatan peninsula through
early next week. Scattered showers and thunderstorms will continue
over the northern Gulf waters through early Sat, then shift
across the NW Gulf Sat through Sun as a frontal boundary stalls
near the northern Gulf coast.

CARIBBEAN SEA...

A broad middle to upper-level low is centered just east of the
Bahamas near 26N74W and extends a trough axis extends
southwestward from there to eastern Cuba and westward to the
Yucatan Peninsula. Upper-level diffluence is enhancing scattered
showers and thunderstorms across the northern Caribbean between
67W and 82W, and has diminished in coverage and intensity
overnight. Scattered thunderstorms are occurring over the SW
Caribbean in association with the east Pacific monsoon trough, and
inside the Gulf of Honduras west of 87W. The remainder of the
basin is not currently experiencing any significant precipitation.

A narrow Atlantic surface ridge extends W-SW along 30-32N and is
supporting moderate to locally fresh trade winds over the basin E
of 80W. Recent ASCAT satellite wind data showed gentle E winds
are occurring over the NW Caribbean. Seas across most of the
basin are 4 to 6 ft except 3 to 4 ft across NW portions.

The Atlantic ridge extends from the central Atlantic W-SW to
northern Florida along 29N this morning, and will drift southward
and weaken through early next week. Moderate to fresh trade winds
over the central Caribbean will weaken to moderate Sat through
Mon, then increase to fresh late Mon through Tue night. Active
weather is possible in the N central Caribbean through the
upcoming weekend as an upper-level trough remains stationary over
the Bahamas and Cuba. A broad surface trough accompanies a
tropical wave across the central Atlantic, and is expected to move
across the Tropical N Atlantic Fri night through Sat night,
across the eastern Caribbean early Sun through early Mon, and
across the central Caribbean Mon through Tue night.

ATLANTIC OCEAN...

A middle to upper-level low is centered near 30N57W then extends
a trough and connects to a broad middle to upper-level low just
east of the Bahamas near 26N74W. Ridging in the low and mid levels
to the north of 27N is allowing for only widely scattered moderate
convection over the area from 28N-31N between 50W and 73W. A 1020
mb high is centered near 29.5N74W and extends a ridge axis from
32N60W to 30N76W to 29N83W. Earlier ASCAT data showed gentle or
weaker winds from 24N-31N between 55W-82W. Seas are generally 3 to
4 ft across that entire area. Moderate trades prevail through the
Bahamas and north of the Greater Antilles, except for fresh north
of Hispaniola and in the Windward Passage. Seas are likely 4 to 5
ft in this area.

The upper-level low centered near 30N57W is enhancing scattered
showers and isolated thunderstorms from 28N-31N between 47W-61W. A
surface trough extending from 31N59N to 29N61W is helping to
converge low level moisture across that area. 1024 mb surface
high pressure is centered near 30N36W. Moderate to fresh trades
and 5-8 ft seas prevail from the monsoon trough to 27N between
30W-55W. Strong NE winds and 7-10 ft seas are likely occurring
from 17N-24N between the coasts of Mauritania/Western Sahara and
27W. Gentle winds prevail from 27N-31N between 25W-55W with 3-5
ft seas.

The narrow Atlantic ridge extending to northern Florida along
29N will weaken and sink southward through early next week as a
frontal boundary moves off the eastern seaboard and stalls NE of
Florida along about 31N. Moderate to fresh E winds S of 25N will
veer to the SE and weaken to gentle early Sat and change little
into next week. Light to gentle variable winds are expected
elsewhere through the period. A tropical wave will reach the
southeast forecast waters by early Sat, bringing a slight increase
in winds and seas over those waters through early Mon.

$$

Stripling
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