265
AXNT20 KNHC 220907
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1215 UTC Fri Aug 22 2025

Tropical Weather Discussion for North America, Central America
Gulf of America, 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
0800 UTC.

...SPECIAL FEATURES...

Large swell associated with Hurricane Erin:
Large northerly swell generated by Hurricane Erin well east of the
U.S. Mid Atlantic coast is causing 12 to 17 ft seas to the
northeast of the Bahamas, from 29N to 31N between 62W and 73W.
Fresh to strong SW to W winds prevail in the same area. As Erin
tracks east-northeastward across the northern Atlantic through
Sunday, these rough to very rough seas will also shift eastward
into the central Atlantic. These swell and seas should gradually
subside starting Sunday evening.

East of the Leeward Islands in the Tropical Atlantic (AL90):
An area of disorganized showers and thunderstorms associated with
a tropical wave is located a couple hundred nautical miles ENE of
the northern Leeward Islands. Environmental conditions appear
conducive for further development of this system, and a tropical
depression is likely to form this weekend while it moves
northwestward and then northward, in between the Lesser Antilles
and Bermuda. This system has a high chance of tropical cyclone
formation, and regardless of development, expecting increasing
winds and building seas with it.

Eastern Tropical Atlantic (AL99):
Showers and thunderstorms associated with a tropical wave located
about a thousand nautical miles west-southwest of the Cabo Verde
Islands remain well organized. This system could become a tropical
depression at any time, but the latest satellite-derived wind data
indicate that the system does not have a well-defined circulation
center. The system is expected to move into a less conducive
environment later today through Saturday, but could reach a
slightly more favorable environment again late this weekend into
early next week as it moves westward at 10 to 15 kt over the
central tropical Atlantic and approaches the Lesser Antilles. This
system has a medium chance for tropical cyclone formation.

Please read the latest Tropical Weather Outlook for more
information regarding both AL90 and AL99 at website:
https://www.nhc.noaa.gov/cyclones/?atl for more details.

...TROPICAL WAVES...

Please see SPECIAL FEATURES above for more on two Atlantic
tropical waves.

A far eastern Atlantic tropical wave is near 18.5W between the
coast of Africa and the Cabo Verde Islands, from 20.5N southward,
moving west around 5 kt. Scattered moderate convection is found
from 09N to 14.5N between the Africa coast and 26.5W.

An eastern Atlantic tropical wave is near 38.5W from 20N
southward through a 1010 mb low (AL99) near 10.5N38.5W, moving
west at 15 to 20 kt. Scattered moderate convection is see from
05.5N to 13.5N between 38.5W and 51W.

A tropical wave is just east of the Lesser Antilles near 59W from
23N southward, moving west around 10 kt. Scattered to numerous
moderate to isolated strong convection is evident from 16N to 24.5N
between 55.5W and 61W.

A Caribbean tropical wave is moving from the central portion of
the basin to the western portion, near the Cayman Islands at 81W
from 20.5N southward to western Panama, moving west at around 20
kt. Convection is described in the Caribbean Sea section below.

...MONSOON TROUGH/ITCZ...

A monsoon trough enters the Atlantic along the Mauritian coast
near EL Mamghar, then curves southwestward through a 1010 mb low
pressure area near 17N21W to another 1010 mb low, AL99, near
10.5N38.5W to 13.5N44W. Refer to the Tropical Waves section
above for convection near the monsoon trough.

...GULF OF AMERICA...

A weak pressure pattern over the area is maintaining light to
gentle winds and 1 to 2 ft seas, except the eastern Bay of
Campeche with moderate E to SE winds and 2 to 3 ft seas. A few
isolated showers and thunderstorms are possible across the basin.

For the forecast, a weak pressure pattern will continue over the
area through the period maintaining quiet marine conditions.
Moderate to fresh northeast to southeast winds will be possible
over the south-central Gulf each afternoon and evening this
weekend into early next week as a trough develops over the Yucatan
Peninsula and moves westward.

...CARIBBEAN SEA...

The pressure gradient between a subtropical ridge building south
of Hurricane Erin in the northwestern Atlantic and low pressure
over Colombia is supporting fresh to strong easterly winds, and
seas of 6 to 8 ft, in the south central Caribbean between 68W and
82W to the south of 18N. Moderate winds, and seas of 3 to 6 ft,
are E of 68W. Gentle to moderate winds and seas of 1 to 3 ft,
prevail over the waters W of 82W. Scattered thunderstorms are in
the SW Caribbean S of 13N and W of 77W near the eastern Pacific
Ocean extension of the monsoon trough. Some showers and
thunderstorms have moved into the NE Caribbean associated with the
tropical wave and AL90 discussed above.

For the forecast, fresh to strong trades and moderate seas,
locally rough, will exist over the central Caribbean through the
next several days as a strengthening pressure gradient develops
between low pressure over Colombia and building high pressure in
the wake of Hurricane Erin in the west Atlantic. Fresh to strong
east to southeast winds will pulse near the Gulf of Honduras at
night. Moderate to fresh trades will pulse in the eastern
Caribbean and across the approach to the Windward Passage with
moderate or weaker winds elsewhere. An area of disorganized
showers and thunderstorms associated with a tropical wave is
located a couple hundred nautical miles ENE of the northern
Leeward Islands. Environmental conditions appear conducive for
further development of this system, and a tropical depression is
likely to form this weekend while it moves northwestward and then
northward, in between the Lesser Antilles and Bermuda. This system
has a high chance of tropical cyclone formation, and regardless
of development, expecting increasing winds and building seas with
it.

...ATLANTIC OCEAN...

Please see the Special Features section at the beginning for
information on Invest Areas AL90 and AL99.

Refer to the Monsoon Trough/ITCZ and Tropical Waves sections for
convection in the Atlantic Basin. Outside the winds and seas
mentioned in the Special Features section, a 1021 mb high near
28N44W is supporting gentle to moderate winds SE to SW to W winds
with 6 to 12 ft seas north of 20N between 65W and the
Florida/southern Georgia coast. To the east, north of 20N between
35W and 65W, gentle to moderate NE to SE winds and seas of 5 to 7
ft exist. For the tropical Atlantic from 10N to 20N west of 35W,
gentle to moderate with locally fresh NE to SE winds and seas at 6
to 7 ft are present. For the remainder of the Atlantic Basin west
of 35W, moderate with locally fresh and seas of 5 to 7 ft in mixed
moderate swell prevail.

For the forecast, Hurricane Erin is centered N of the area and
continues to move NNE away from the region. Despite its distance,
long period northerly swells generated by Erin will continue to
affect the W Atlantic waters through the next few days. In the
wake of Erin, central Atlantic high pressure will build WSW toward
the central Bahamas and the Straits of Florida. An area of
disorganized showers and thunderstorms associated with a tropical
wave is located a couple hundred nautical miles ENE of the
northern Leeward Islands. Environmental conditions appear
conducive for further development of this system, and a tropical
depression is likely to form this weekend while it moves
northwestward and then northward, in between the Lesser Antilles
and Bermuda. This system has a high chance of tropical cyclone
formation, and regardless of development, expecting increasing
winds and building seas with it E of 70W.

$$
Lewitsky