[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 212310
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0005 UTC Sat Jul 22 2023

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
2300 UTC.

...SPECIAL FEATURES...

Tropical Storm Don is centered near 35.8N 46.5W at 21/1500 UTC
or 940 nm W of the Azores moving WNW at 9 kt. Estimated minimum
central pressure is 1002 mb. Maximum sustained wind speed is 45
kt with gusts to 55 kt. Scattered moderate convection is noted
up to 60 nm in a southern semicircle from the center. Since the
time, the convection has become somewhat more fragmented, but
there is still a well-defined curved band that wraps about three-
quarters of the way around Don's center. Seas are peaking to 20 ft
near the center. A turn toward the northwest with a slightly
faster forward speed is expected later today. A north-
northwestward to northward motion is forecast on Saturday,
followed by a north-northeastward turn by late Sunday. Little
overall change in strength is forecast during the next day or so.
Weakening is forecast to begin by Sunday morning.

Please read the latest HIGH SEAS
FORECAST issued by National Hurricane Center at web-site
https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the latest T.S.
Don Forecast/Advisory and Public Advisory at www.hurricanes.gov
for more details.

Central Tropical Atlantic (AL95):
A 1012 mb low pressure is centered near 12N40W. The low is
producing an area of disorganized showers and thunderstorms over
the central tropical Atlantic. Although there is dry air located
to the north of the system, favorable upper- level winds are
expected to allow for gradual development during the next several
days. This system could become a tropical depression early next
week, as it moves westward across the tropical Atlantic. Refer to
the latest Tropical Weather Outlook at www.hurricanes.gov for more
details.

Gale Warning E of 35W: Meteo-France is forecasting frequent gusts
to gale force and rough to very rough seas mainly in the east part
of the Agadir Marine Zone. Please read the High Sea Forecast and
Warning at https://wwmiws.wmo.int for more information.

...TROPICAL WAVES...

An eastern Atlantic tropical wave extends its axis along 30W from
06N to 18N. Scattered showers are noted along the wave axis,
mainly over the southern half of the wave.

A central Caribbean tropical wave has its axis along 79W south of
W Jamaica to inland eastern Panama, moving westward around 15 kt.
No significant convection is noted over the western Caribbean
associated to this wave at this time.

...MONSOON TROUGH/ITCZ...

The monsoon trough enters the Atlantic near 18N16W to the low near
12N40W described above, to 08N47W. Aside from convection noted in
the SPECIAL FEATURES and the TROPICAL WAVES sections above,
scattered moderate convection is noted from 05N to 11N and E of
25W.

...GULF OF MEXICO...

A surface trough is located over the central Gulf from 28N87W to
26N89W enhancing scattered showers in the area. To the SW, a
larger area of scattered to numerous moderate convection has
developed over the Yucatan peninsula and is moving W across the
Bay of Campeche S of 22N and E of 91W. Elsewhere, broad and weak
high pressure is present over the region. The associated gradient
is allowing for generally light to gentle winds and seas of 1-3 ft.

For the forecast, the aforementioned high pressure will remain
remain dominate into early next week. This will support mainly
gentle to moderate winds, except over the eastern Bay of Campeche
where winds will be enhanced by a thermal trough coming off the
Yucatan Peninsula during the overnight hours.

...CARIBBEAN SEA...

Convergent easterly trade winds are coupling with mid-level
troughing leading to scattered showers and thunderstorms over the
northwest section of the basin mainly W of 83W. Elsewhere,
GOES-16 Saharan Air Layer Tracking product is showing an area of
Saharan dust moving west across the Atlantic Ocean and into the
central Caribbean reaching central Cuba. Therefore, expect above
normal temperatures with dry conditions, hazy skies, and patches
of lower visibility to continue. A tight pressure gradient between
the Bermuda High and Colombian Low is maintaining strong to near-
gale easterly winds along with seas of 8-11 ft over the south-
central part of the basin north of Colombia. Fresh to strong east
winds and seas of 6-9 ft are over the north- central part of the
basin. Gentle to moderate northeast to east winds with seas of 6-8
ft due to an easterly swell. Moderate to fresh easterly trades
and seas of 3-6 ft seas are elsewhere in the basin.

For the forecast, the aforementioned mentioned pressure gradient
between the Bermuda High and lower pressure over Central America
and northern South America will maintain strong trades across the
central Caribbean through Sat night. Winds should diminish slight
to fresh to strong Sun through Tue night. Fresh to locally strong
trades will develop over the Gulf of Honduras Sun through Mon. Low
pressure developing east of the region is forecast to move into
Atlantic waters E of the Lesser Antilles early next week, possibly
bringing enhanced winds and seas.

...ATLANTIC OCEAN...

Please see the SPECIAL FEATURES, TROPICAL WAVES, and the MONSOON
TROUGH/ITCZ sections for more information on Tropical Storm Don in
the north-central Atlantic, gale winds in the eastern Atlantic,
and convection in the tropical Atlantic.

Scattered moderate convection is noted north of 21N between 62W
and 68W in association with an upper-level disturbance. Another
area of similar convection is north of 29N and W of 69W. Elsewhere,
GOES-16 Saharan Air Layer Tracking product is showing an area of
Saharan dust moving west across the Atlantic Ocean. Therefore,
expect above normal temperatures with dry conditions, hazy skies,
and patches of lower visibility.

Light to gentle winds and seas of 3 to 5 ft north of 24N between
43W and the Georgia-Florida coast, outside of convection. To the
south, moderate with locally fresh northeast to east to east-
southeast winds and seas at 4-6 ft are noted from 20N to 23N and
between 43W and the Bahamas. Farther east, the Azores High is
channeling gentle to moderate northeast winds with 5-7 ft seas
north of 20N between 25W-20W. Near the Canary Islands, moderate to
fresh with locally strong north to northeast trade winds and seas
of 7-9 ft are present. North of 16N between the Africa coast and
35W moderate northeasterly winds and seas 4-6 ft are seen. For the
tropical Atlantic, gentle to moderate northeast to east trades
and seas of 4-6 ft are present. Gentle to moderate southerly and
monsoonal westerly winds along with seas of 4-6 ft prevail for the
remainder of the Atlantic Basin.

For the forecast west of 55W, the Bermuda High will weaken
through the weekend. Fresh trades just north of Hispaniola and
over the Windward Passage will diminish tonight. Elsewhere across
forecast waters, winds will be moderate or weaker into Tue night.

$$
ERA
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