[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 131035
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1205 UTC Sat Aug 13 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...

A tropical wave is analyzed with axis along 21W from 05N-20N,
moving W at 10 kt. A 1009 mb low pressure is near the wave axis
at 14.5N19.5W. Scattered moderate to strong convection is noted
from 13N-18.5N between 22W and the west coast of Africa, and
from 08N-11N between 17W and the west coast of Africa.

A tropical wave extends its axis along 54-55W from 24N southward,
moving W at 15-20 kt. A broad surface trough is associated with
this tropical wave. A large plume of atmospheric moisture
accompanies this wave between 48W and 57W, as noted in Precipitable
Water imagery, while Saharan Air dominates the environment between
57w and 62W. Scattered moderate isolated strong convection is
noted from 08.5N to 15N between 48W and 56W.

A weak tropical wave has an axis over the eastern Caribbean along
63-64W from 17N southward to SE Venezuela, moving W at 15 kt.
Widely scattered moderate convection is noted from 10N-12.5N
between 58W-62W. Saharan Air has engulfed much of this wave and
extends from 57W to 69W.

A central Caribbean tropical wave has an axis along 77-78W from
Jamaica to western Colombia, moving W at 10-15 kt. Isolated
moderate convection is over the waters of Haiti, eastern Cuba and
Jamaica. Father south, scattered moderate to strong convection
is noted from 11.5N southward over northwestern Colombia between
75W-79W.

...MONSOON TROUGH/ITCZ...

The monsoon trough extends from the coast of southern Mauritania
near 17N16.5W to a 1009 mb low near 14.5N19.5W to 11N25W to
14N46W to 11N56W. The ITCZ continues from 11N56W to the coast of
Brazil near 10N62W. Aside from the convection described in the
Tropical Waves section above, scattered moderate isolated strong
convection is noted within 240 nm S of the trough between 24W-38W.

GULF OF MEXICO...

A surface trough of low pressure extends over the northwest Gulf
of Mexico from SE Louisiana to 27N97W. Low to middle level
cyclonic turning across the NW Gulf continues to produce moisture
convergence. The coverage of showers and thunderstorms has again
tonight compared to the daytime on Friday. Widely scattered
moderate convection is noted across the NW Gulf, from 23N
northward to 29N and between 91.5W and the coasts of Texas and
northeast Mexico. Elsewhere a 1017 mb high pressure is centered
over the NE Gulf near 29N86W. Gentle winds prevail across the
eastern Gulf, while moderate to locally fresh winds prevail near
the surface trough and over the Bay of Campeche. Recent buoy and
altimeter data across the basin are showing seas of 2 to 3 ft.
However, seas up to 4 ft may be occurring just east of the surface
trough in the northwest Gulf, and to the west of the Yucatan
Peninsula.

For the forecast, low pressure is likely to reform along the
surface trough in the NW Gulf later today. This system will drift
west-southwestward and approach the Texas coast this afternoon,
and move inland over southern Texas on Sun. This system is
expected to produce scattered to numerous showers and
thunderstorms today through tonight over the northwest Gulf.
Strong gusty winds and rough seas can be expected with this
activity. Moderate NE to E winds will pulse to fresh during the
late afternoon and evenings off the NW Yucatan peninsula through
early next week. Meanwhile, a weak frontal boundary is expected to
stall just north of the central and NE Gulf through Sun.

CARIBBEAN SEA...

Satellite imagery shows scattered showers and isolated
thunderstorms near Haiti, Jamaica, and Cuba due to the influences
of upper-level troughing and a tropical wave in the area, and .
also offshore of the NE coasts of Nicaragua and Honduras. That
tropical wave is also producing convection near the coasts of
Colombia and NW Venezuela, described above in the tropical waves
section. Earlier ASCAT satellite wind data showed fresh trade
winds in the south- central Caribbean, south of 15N between 67W-
71W, where seas are 4-6 ft. Moderate trades prevail elsewhere east
of 76W with 4-5 ft seas. Gentle to moderate winds prevail west of
76W with 2-5 ft seas.

The Atlantic high pressure ridge along 29-30N will drift
southward and weaken through early next week. Moderate to fresh
trade winds over the central Caribbean will weaken to moderate Sat
afternoon through Mon, then increase to fresh late Mon through
Wed. A broad surface trough accompanying a tropical wave entering
the Tropical N Atlantic waters this morning, will move across the
Lesser Antilles this evening, across the eastern Caribbean early
Sun through early Mon, then across the central Caribbean Mon
through late Wed. Trade winds will strengthen late Tue through Wed
as high pressure repositions near 27N65W.

ATLANTIC OCEAN...

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

A surface ridge axis extends from 1024 mb high pressure near
31N42W to 32N57W to 1017 mb high pressure in the NE Gulf near
29N86W. Earlier ASCAT satellite wind data showed gentle
anticyclonic winds along and within 300 nm S of the ridge axis,
including over the NW Bahamas. Seas are likely near 3 ft in this
area, west of 60W. Mid- to upper-level troughing is occurring over
most of the area where the surface ridge is. As a result,
scattered moderate convection is noted from 26N-33N between 42W-
55W. Scattered clusters of moderate to strong convection extends
north of a lone from 27.5N80.5W east-northeastward to beyond
31N69W. Isolated showers and tstorms are also noted across the
southern Bahamas. Moderate trades prevail south of 23N to the
north of Hispaniola and over the southeastern Bahamas, where seas
are 3-5 ft.

The broad 1009 mb low along the monsoon trough near 14.5N19.5W is
accompanied by moderate winds. However, recent ASCAT satellite
wind data showed fresh to locally strong SW winds to the south
from 05N-11.5N between 15W-23W. Fresh NE winds are occurring to
the north, covering the area between the Cabo Verde Islands and
the Canary Islands. Altimeters passing over the area have measured
seas of 7 to 8 during the past 6 to 12 hours, from 15N-22N
between 30W and the coast of Africa. Moderate to fresh trades and
5-7 ft seas prevail from 14N-24N between 30W-60W.

For the forecast W of 55W, the western Atlantic ridge will weaken
and sink southward through early next week as a frontal boundary
moving off the SE U.S coast stalls just N of the area. Moderate to
fresh E winds S of 24N will veer to the SE and weaken to gentle
to moderate today and change little through Wed. A broad tropical
wave will enter the southeast forecast waters today, bringing a
slight increase in winds and seas over those waters tonight
through early Mon. A cold front will move over the waters
northeast of NE Florida late Tue, then stall and weaken through
Wed night.

$$
Stripling
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