Tropical Weather Discussion
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268
AXNT20 KNHC 040547
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0615 UTC Sat Oct 4 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 0000 UTC surface analysis and satellite imagery through
0547 UTC.

...SPECIAL FEATURES...

Significant Swell Event over the Western and Central Atlantic:

Large northerly swell generated by hurricane force winds
associated with previous Tropical Cyclones Imelda and Humberto in
the northern Atlantic are propagating across the forecast waters
S of 31N building seas to 16 to 18 ft over the central Atlantic.
Seas 12 ft or greater dominate a large area, particularly N of 23N
between 43W and 73W. Altimeter data and buoy observations
confirmed the presence of these sea heights. This swell event will
continue to expand southward this weekend, leading to widespread
rough seas north of 10N. Very rough seas in excess of 12 ft are
expected north of 23N this weekend, including near the northern
Bahamas. In addition, this swell event will also sustain dangerous
surf conditions, significant beach erosion and probable local
coastal inundation along the east- facing shores of Georgia and
Florida, the north and east-facing shores of the Bahamas, and the
north- facing shores across Hispaniola, Puerto Rico, the Virgin
and Leeward Islands. Refer to your local weather agencies for the
latest statements.

Please read the latest NWS High Seas Forecast issued by the
National Hurricane Center at website
https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for further
details.

...TROPICAL WAVES...

A tropical wave emerged yesterday afternoon off the coast of
Africa. Its axis is along 18W. A cluster of moderate to isolated
strong convection is depicted from 11N to 14N and east of 19W.
Scattered moderate convection is found from 06N to 08N between 16W
and 18.5W. The wave is forecast to interact with another
disturbance over the eastern tropical Atlantic, and then move
westward after that. Environmental conditions are expected to
become conducive for some slow development of the system in a few
days, and a tropical depression could form near or east of the
Lesser Antilles by the end of next week. There is a medium chance
of tropical development within the next 7 days.

A central Atlantic tropical wave is near 40W from 20N southward.
It is moving west at around 10 kt. Dryness at low to mid levels
are prohibiting significant convection near this wave.

Another tropical wave is east of the Lesser Antilles near 54.5W
from 20N southward, and moving west around 5 kt. Scattered showers
and isolated thunderstorms are noted E of the wave axis from 13N
to 17N between 47W and 52W.

...MONSOON TROUGH/ITCZ...

The monsoon trough enters the Atlantic Ocean near 13N17W, then
continues southwestward to 06N26W and northwestward to 13N45W.
Numerous moderate to isolated strong convection is present from
02N to 13N between 18W and 30.5W.

...GULF OF AMERICA...

An old frontal boundary is producing scattered moderate convection
north of 26N between 83W and 91W. A surface trough over the Bay
of Campeche is supporting numerous showers, with embedded
thunderstorms, across the central and eastern Bay of Campeche, and
north of the Yucatan Peninsula. Fresh to strong NE to E winds,
and moderate seas dominate the NE and N Gulf due to the pressure
gradient between high pressure over the eastern United States and
an old frontal boundary meandering across the Bahamas, south
Florida, and across the eastern Gulf. Fresh N winds and seas of 4
to 6 ft are occurring near and offshore of Veracruz, Mexico.
Gentle to moderate NE to E winds and slight to moderate seas
prevail elsewhere.

For the forecast, fresh to strong NE to E winds and locally rough
seas will prevail over the northern Gulf, mainly north of 26N,
tonight into early Sun, as a strong pressure gradient prevails
between high pressure across the eastern U.S. and an old frontal
boundary meandering across the Bahamas, south Florida, and across
the eastern Gulf. This boundary will begin to lift northward as a
warm front in the central Gulf early Sun and into the southeastern
United States Mon, supporting slowly diminishing winds over the
northern basin. Moderate E to SE winds and slight to moderate seas
are expected over the rest of the Gulf into next week.

...CARIBBEAN SEA...

A weak pressure gradient dominates the Caribbean Sea supporting
moderate to locally fresh trades across the south-central
Caribbean, and light to gentle winds elsewhere. Slight seas
prevail across the basin, except for higher seas of 6 to 7 ft in
N swell across the NE Atlantic passages, including the Mona and
Anegada Passes. An upper-level low is spinning over Hispaniola,
with an upper- level trough extending to eastern Panama. These
features are enhancing convection over most of the western half of
the basin, including Hispaniola, Jamaica and eastern Cuba as well
as parts of the south-central Caribbean and central America.

For the forecast, gentle to moderate trade winds will prevail
over most of the Caribbean Sea into next week as a weak pressure
gradient persists across the region. Large N to NE swell,
generated by previous Tropical Cyclones Imelda and Humberto, will
continue to produce rough seas in the Atlantic Passages and over
the waters E of the Lesser Antilles into early next week. Seas
will slowly subside early next week. Looking ahead, moderate to
occasionally fresh E to SE winds will pulse in the Gulf of
Honduras Sat night into early next week.

...ATLANTIC OCEAN...

Please read the Special Features section at the very beginning about
large northerly swell.

The pressure gradient between high pressure over the eastern
United States and an old frontal boundary and weak area of low
pressure near the Bahamas is supporting fresh to strong NE to E
winds off the coast of Florida and over the northern Bahamas,
generally north of 25N and west of 70W. Farther east, a cold front
enters the forecast area near 31N47W, then continues SW to near
23N61W where it becomes a stationary front that extends to a 1011
mb low pressure located over the central Bahamas. In addition, a
pre frontal trough is analyzed from 31N44W to 24N56W. Scattered
showers and thunderstorms are near the front and the pre frontal
trough, more concentrated near the stationary front. Fresh to
strong SW winds are N of 29N and E of the front to about 41.5W.
North of the front, moderate to fresh winds prevail. Very rough
seas, in northerly swell, follow the front. An upper-level trough
is generating some convective activity north of 26N between 22W
and 29W. Gentle to moderate winds are observed over the tropical
Atlantic.

For the forecast west of 55W, fresh to strong NE winds will
continue off the coast of Florida and over the northern Bahamas,
generally north of 25N and west of 70W, tonight into early next
week, as an old frontal boundary and weak area of low pressure
meanders across the NW Bahamas and south Florida over the next
several days. Farther east, fresh NE to E winds are expected north
of a cold front extending from 26N55W to 23N66W to the NW Bahamas
into Sun. The front will lift northward and weaken this weekend.
Large N to NE swell generated by previous Tropical Cyclones Imelda
and Humberto will continue to propagate southward this weekend,
leading to widespread rough seas north of 10N. Seas in excess of
12 ft are expected north of 23N this weekend, including near the
northern Bahamas. Looking ahead, a tropical wave has just emerged
off the coast of Africa. The wave is forecast to interact with
another disturbance over the eastern tropical Atlantic, and then
move westward after that. Environmental conditions are expected to
become conducive for some slow development of the system in a few
days, and a tropical depression could form near or east of the
Lesser Antilles by the end of next week.

$$
KRV