[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 241104
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1205 UTC Mon Jul 24 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 0600 UTC surface analysis and satellite imagery through
1045 UTC.

...SPECIAL FEATURES...

Tropical Storm Don is centered near 47.0N 43.0W at 24/0900 UTC,
or about 410 nm E of Cape Race Newfoundland moving ENE at 16 kt.
Estimated minimum central pressure is 1005 mb. Maximum sustained
wind speed is 40 kt with gusts to 50 kt. Satellite imagery shows
that the earlier observed minimal convection that was in the SE
quadrant of Don has since dissipated, and Don is becoming a large
cyclonic swirl of mostly overcast to broken mostly low and mid-
level clouds. Peak seas are up to 25 ft near the center. Don is
forecast to maintain its current motion as it continues to weaken.
It is expected to become a post-tropical cyclone later today.

Please read the latest HIGH SEAS FORECAST issued by National
Hurricane Center at website
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.

...TROPICAL WAVES...

A far eastern Atlantic tropical wave has its axis along 26W from
03N to 18N. It is moving westward at 10 kt. Scattered moderate
convection is seen from 06N to 10N and between the wave and 34W.

A central Atlantic tropical wave has its axis along 42W from
03N to 19N, moving westward at 10-15 kt. Scattered moderate
convection is from 04N to 09N between 40W-45W.

...MONSOON TROUGH/ITCZ...

The monsoon trough reaches the Atlantic through the coast of
Mauritania near 19N16W. It continues southwestward to 09N30W to
09N40W, to a 1012 mb low pressure (Invest 95L) near 11N50W and
to 12N55W, where it transitions to the ITCZ to near 10N61W.
Aside from convection associated to the tropical waves as
described above, scattered moderate to isolated strong convection
is seen from 08N to 14N between the coast of Africa and 21W.
Scattered moderate convection is within 180 nm south of the trough
between 45W-48W and within 120 nm south of the trough between
30W-38W.

...GULF OF MEXICO...

A few showers and isolated thunderstorms are found in the northern
Gulf of Mexico, primarily in the north-central Gulf, due to a
weak stationary front draped across the northern Gulf coast.
Farther south, increasing numerous moderate to strong convection
over the Bay of Campeche, and is reaching northward to near 21N.
The rest of the basin is dominated by a 1020 mb high pressure
located west of Florida. Moderate to fresh northeast to east winds
are evident off NW Yucatan, mainly south of 25N and east of 95W.
Seas in these waters are 3-4 ft. Elsewhere, light to gentle
anticyclonic winds and seas of 1-3 ft prevail.

For the forecast, weak high pressure centered near the Florida
Peninsula will remain dominant the feature for the Gulf through
midweek. This will support mainly gentle to moderate winds, except
over the eastern Bay of Campeche where winds will be enhanced by
a thermal trough that will emerge off the Yucatan Peninsula
nightly. A stationary front just inland the northern Gulf coast
will provide a focus for showers and thunderstorms in adjacent
waters for the next few days.

...CARIBBEAN SEA...

The pressure gradient between the subtropical ridge north of the
Caribbean and lower pressures in northern South America and
Central America is sustaining  strong to locally near gale-force
easterly trade winds in the south-central Caribbean and the Gulf
of Honduras. A partial overnight ASCAT pass highlighted these
winds over the eastern part of the south-central Caribbean. Seas
over this section of the sea are 6-9 ft, with the highest seas
noted off NW Colombia. Moderate to fresh easterly winds and seas
of 3-6 ft are found in the eastern and north-central Caribbean.
Light to gentle easterly breezes and slight seas prevail
elsewhere.

The earlier noted scattered showers and thunderstorms over the
southwestern Caribbean have shifted inland Nicaragua.

The Saharan Air Layer (SAL) airmass is suppressing the
development of showers and thunderstorms over some sections of the
sea.

For the forecast, the pressure gradient between the Bermuda High
and lower pressure over Central America and northern South America
will maintain strong trades across the central Caribbean tonight.
Winds should diminish slightly to fresh to strong today through
Wed night. Fresh to locally strong trades will occur over the
Gulf of Honduras into Mon night. Low pressure, Invest AL95, over
the tropical N Atlantic about 560 nm east of the Windward
Islands is expected to weaken to a trough early this week as it
approaches those islands. Some slow development of the low
remains possible during the next couple of days while it moves
westward across the tropical Atlantic and eastern Caribbean Sea.
Expect increasing winds and seas with the low and the subsequent
trough.

...ATLANTIC OCEAN...

Please see the SPECIAL FEATURES section for information on
Tropical Storm Don in the north-central Atlantic.

A 1012 mb low pressure system, designated as Invest 95L, is
located near 11N50W or about 560 nm east of the Windward Islands.
Latest satellite imagery shows numerous moderate to strong
convection increasing quite rapidly ahead of the low from 09N
to 17N between 51W-57W. Scattered moderate to isolated strong
convection is over the low and extends to northwest of the low
to 13N and between 48W-51W. Fresh to strong easterly winds are
in the N quadrant of the low. Seas over these waters are 5-8 ft.
While this system has not become any better organized recently,
some slow development remains possible during the next couple of
days while it moves westward across the tropical Atlantic and
eastern Caribbean Sea. Environmental conditions are expected to
become unfavorable for development by the middle of the week.
Locally heavy rainfall is possible across the Windward Islands
early this week from this system. This disturbance has a low
chance of development in the next 48 hours. Please refer to the
latest Tropical Weather Outlook at www.hurricanes.gov for more
details.

Elsewhere, a surface trough is analyzed northeast of Puerto Rico
along 65W/66W and from 22N to 26N. Divergence aloft is inducing
the development of scattered showers and thunderstorms from
22N to 30N and between 60W-72W. Farther west, a few showers and
isolated thunderstorms are noted off central Florida and near the
NW Bahamas. The remainder of the SW Atlantic is under the western
periphery of the subtropical ridge in the central Atlantic.
Moderate to locally fresh easterly trade winds are occurring south
of 22N and between 65W-75W. Seas in the area described are 2-4
ft. Elsewhere west of 60W, light to gentle anticyclonic winds and
slight to moderate seas are prevalent.

A broad 1031 mb high pressure system located well north of the
area near 38N41W dominates the central and eastern Atlantic,
maintaining fairly tranquil weather conditions. Dry Saharan dust
is also moving across the area, contributing to the suppression of
the development of deep convection. Moderate to fresh easterly
winds and seas of 5-8 ft are evident north of the monsoon trough
to 31N and between coast of Africa and 60W. Elsewhere, light to
gentle winds and moderate seas prevail.

For the forecast west of 55W, weak high pressure over the area
will change little through early Tue, then shift to just north of
the area through the rest of the week. Fresh trades will pulse
nightly N just N of Hispaniola and over the Windward Passage.
Elsewhere across forecast waters, winds will be moderate or weaker
over most of the area with moderate to locally fresh speeds for
waters NE of the Leeward Islands. Scattered showers and
thunderstorms generated by a trough are present from 22N to 30N
between 60W-72W.

$$
Aguirre
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