[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 241040
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1205 UTC Wed Aug 24 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
1030 UTC.

...TROPICAL WAVES...

A central Atlantic tropical wave has its axis along 38W from 03N
to 20N moving westward at 10 kt. Scattered moderate convection is
within 180 nm west of the wave from 14N to 17N. Otherwise, the
environment surrounding this wave remains rather dry limiting
deep convection from forming.

A western Atlantic tropical wave has its axis along 57.5W from
03N to 20N moving westward at 5 kt. This wave is part of a
broad trough of low pressure that is east of the Windward Islands.
Scattered moderate to isolated strong convection is within 120 nm
west of the wave from 06N to 09N. Scattered moderate convection
is within 150 nm east of the wave from 06N to 09N. Scattered
showers and isolated thunderstorms are within 150 nm east of the
wave from 11N to 13N. Environmental conditions could become more
conducive for slow development of this system in several days
while it is forecast to move across the Windward Islands and into
the southeastern Caribbean Sea.

A western Caribbean tropical wave has its axis along 87W south of
20N moving westward at about 10 kt. Scattered showers and thunderstorms
are lagging behind the wave from 15N to 18N between 79W-83W. Isolated
showers and thunderstorms are elsewhere west of 78W.

...MONSOON TROUGH/ITCZ...

The monsoon trough axis extends from the coast of Mauritania near
18N16W southwestward to 14N23W, then to 15N35W to 11N45W and to
09N60W. Increasing numerous moderate to strong convection is south
of the trough from 08N to 13N between 20W-26W, and from 06N to 10N
between 26W-30W. Scattered moderate convection is within 120 nm
south of the trough between 47W-50W.

GULF OF MEXICO...

The broad base of an upper-level trough is situated just inland
the NE and north-central Gulf, while a stationary frontal
boundary is analyzed from near 29N85W northwestward to inland
southeastern Louisiana. This boundary is serving as the focus
for rounds of scattered showers and thunderstorms that form along
it and track in an eastward direction. As shortwave troughs move
through the upper-level trough, expect for this activity to remain
quite active through the next couple of days as the present
synoptic pattern changes little. Meanwhile, diffluent flow aloft
is supporting isolated showers over the far eastern Gulf waters
north of 26N. A surface trough is just along the western section
of the Yucatan Peninsula. The earlier noted scattered moderate
convection in the Bay of Campeche has diminished to mainly
isolated showers. An overnight ASCAT data pass indicated gentle
to moderate northeast to east winds across and near this trough,
including the eastern Bay of Campeche. Otherwise, relatively weak
high pressure remains over the area. The associated gradient is
supporting gentle to moderate winds and 1-3 ft seas across the
Gulf.

For the forecast, relatively weak high pressure will remain over
the area through the forecast period maintaining gentle to
moderate winds and slight seas. Moderate to fresh NE to E winds
will pulse near and to the W of the Yucatan peninsula due to
local effects during the late afternoons and at night through
Thu.

CARIBBEAN SEA...

Abundant deep layer moisture is present in the basin. Aside from
the shower and thunderstorm that is near the tropical wave along
87W, small clusters of similar activity moving westward is over
the central part of the sea from 15N to 17N between 69W-72W, and
scattered showers and isolated thunderstorms are most sections of
the eastern Caribbean. Isolated showers and thunderstorms, also
moving westward are seen elsewhere across the sea, with the
exception of the far southwestern part of the sea where scattered
showers and isolated thunderstorms are occurring. Winds are
generally gentle to moderate from the east with 2-4 ft seas.

For the forecast, high pressure over the central Atlantic will
continue to support moderate to fresh trade winds in the eastern
and central Caribbean through the forecast period, while gentle to
moderate winds will continue across the western Caribbean. A
tropical wave accompanied by scattered showers and thunderstorms
is moving through the Tropical N Atlantic waters, and was
analyzed along 57.5W at 0600 UTC. The wave is expected to reach
the Lesser Antilles Wed night, then move through the eastern
Caribbean Thu through Fri night and the central Caribbean Sat
through Sun night.

ATLANTIC OCEAN...

The Bermuda-Azores High is the main feature across the Atlantic
subtropical waters. The western Atlantic is generally under
a gentle to moderate southeast wind flow, with seas in the
3-5 ft range. A surface trough is analyzed from near 30N65W to
25N70W as highlighted in an overnight ASCAT data pass. This
pass shows a very noticeable wind shift across the trough axis,
with moderate to fresh southeast to south winds east of the
trough to near 63W and light to gentle northeast to east winds
west of the trough to near 72W. In addition, the trough continues
to be underneath a large and persistent upper-level low that is
located near 25N68W per latest satellite water vapor imagery.
In the central Atlantic, a weakening cold front extends from
a 1018 mb low north of the area near 37N33W southwestward to
33N41W and to 32N45W, then becomes stationary to 32.5N40W.
Scattered moderate convection is near the low pressure, and
also from 32N to 35N between 34W-38W. Isolated small showers
and thunderstorms are seen from 30N to 32N between 40W-49W,
and from 30N to 33N between 53W-56W. All of the activity is moving
to the south, except for the activity from 30N to 33N between
53W-56W, which is moving westward. Winds in the central Atlantic
mainly moderate and east in direction, except for light to gentle
east winds north of 27N between 40W-62W as a 1023 mb high center
is just north of the area near 33N57W. Seas in this part of the
Atlantic are in the 4-6 ft range. The pressure gradient is tighter
in the eastern Atlantic, supporting moderate to fresh northeast
winds and seas of 6-8 ft. Stronger winds of fresh to strong speeds
are along and within about 180 nm northwest of the coast of
Africa from 21N to 28N. Seas are also 6-8 ft with these winds.

For the forecast W of 55W, the aforementioned surface trough
will move westward toward the Bahamas through Thu accompanied by
scattered to numerous showers and thunderstorms. Winds and seas
may be higher in and near scattered showers and thunderstorms.
Relatively weak high pressure will build in the wake of the trough
allowing for generally a gentle to moderate east to southeast flow
beginning on Wed. Scattered showers and thunderstorms are expected
over the NW forecast waters during the weekend as a front stalls
across north-central Florida and extends northeastward over those
waters.

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