626
AXNT20 KNHC 172314
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0015 UTC Sat Oct 18 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 1800 UTC surface analysis and satellite imagery through
2300 UTC.

...SPECIAL FEATURES...

Atlantic Large Swell Event:
Northerly swell generated from a storm force low over the Atlantic
waters north of the discussion area will support rough to very rough
seas over the western Atlantic through this weekend. Seas in
excess of 12 ft and greater seas will continue to spread
southeastward on Sat, covering the waters north of 27N between 43W
and 70W by Sat night. The swell will then start to subside over
the discussion waters allowing for seas to drop below 12 ft Sun
night. Seas with this swell will peak near 18 ft over the waters
north of about 30N between 50W and 65W on Sat.

Please read the latest HIGH SEAS FORECAST issued by the National
Hurricane Center at website -
https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details.

...TROPICAL WAVES...

A far-eastern Atlantic tropical wave has been introduced to this
analysis, with axis along 16W from 00N-11N, moving W at around 10
kt. Scattered showers are noted along the wave axis.

A central Atlantic tropical wave has also been introduced to this
analysis, with axis along 30N and S of 08N, moving W at 10 kt.
Scattered moderate to strong convection is from 01N-08N between
25W-36W.

A central Atlantic tropical wave is near 44W from 16N southward,
moving westward at around 15 kt. Scattered moderate to isolated
strong convection is noted from 06N to 12N between 41W and 49W.
Gradual development of this system is possible over the next
several days while it moves generally westward at 15 to 20 kt.
Regardless of development, this system is expected to bring heavy
rainfall and gusty winds to the Windward Islands late this weekend
and then move across the Caribbean Sea much of next week. This
wave has a low chance of tropical cyclone formation in the next 48
hours.

A central Atlantic tropical wave is near 53W from 16N southward,
moving westward near 10 kt. Scattered moderate to isolated strong
convection is noted from 08N to 13N between 52W and 59W.

...MONSOON TROUGH/ITCZ...

The monsoon trough enters the Atlantic near 12N16W and extends
southwestward to near 04N35W. Aside from convection noted in the
tropical waves section, scattered moderate to isolated strong
convection is noted from 01N to 09N between 19W and 25W.

...GULF OF AMERICA...

Surface ridging prevails across the basin, anchored by a 1018 mb
high pressure centered over South Carolina. Gentle to moderate E
to SE winds prevail across most of the basin, except over the Bay
of Campeche where light and variable winds are noted. Slight to
moderate seas prevail across the basin.

For the forecast, moderate E to SE winds and slight to moderate
seas are expected over much of the Gulf through late Sat as high
pressure prevails over the southeastern United States.
Occasionally fresh E winds will be possible in the central and
eastern basin. A cold front is slated to enter the northwestern
Gulf on Sun and progress southeastward through the basin into
early next week, and moderate to locally fresh N to NE winds are
expected in the wake of the front Sun into Mon. Generally moderate
NE to SE winds and slight to moderate seas will return over the
Gulf early next week as weak ridging builds over the region.

...CARIBBEAN SEA...

A frontal trough extends from Hispaniola, to the Yucatan Passage.
Satellite imagery shows clusters of showers and thunderstorms
along and near this boundary. A weak pressure gradient is across
the Caribbean waters supporting gentle to moderate winds E of 65W,
and light to gentle winds elsewhere. Slight seas prevail across
the basin.

For the forecast, gentle to moderate winds and slight seas are
expected over the Caribbean Sea through Sat. Moderate to fresh E
to NE winds and moderate seas will develop over the eastern
Caribbean Sat night and extend into the central basin on Sun as a
tropical wave moves westward over the region. A second, stronger
tropical wave is slated to move through the central Atlantic this
weekend, entering the eastern Caribbean early next week. Fresh to
strong winds and rough seas will accompany the wave as it passes
over the waters east of the Leeward Islands on Sun, with
increasing winds and building seas developing in the eastern basin
Sun night into early next week. This system has a low chance of
tropical development within the next 48 hours and next 7 days.
Regardless of development, this system is expected to bring heavy
rainfall and gusty winds to the Windward Islands late this weekend
and then move across the Caribbean Sea much of next week.

...ATLANTIC OCEAN...

Please refer to the Special Features section for further details
on a large swell event that will continue to impact some sections
of the north-central waters through the weekend.

A cold front extends from 31N45W to 19N66W, then becomes a trough
to Hispaniola. Fresh to strong SW winds, and rough seas are N of
20N and E of the front to 40W. A reinforcing front extends from
31N56W to 24N76W. Fresh to strong NW winds and seas of 8-12 ft
are W of the front. Moderate to fresh winds, and rough seas are
noted between the fronts. High pressure dominates the remainder
of the discussion waters N of 20N, anchored by a 1018 mb high near
24N33W. Light to gentle winds are around the high center. Gentle
to moderate winds prevail elsewhere. Seas are in the moderate range.

For the forecast W of 55W, fresh to strong SW winds, with
localized near-gale force winds, will occur over the central
Atlantic north of 20N and east of 60W through Sat morning as a
cold front slowly migrates eastward. The second/reinforcing cold
front will propagate eastward through this weekend, and fresh to
strong N to NW winds will occur in the wake of the front north of
25N and east of 75W through Sun morning. Widespread rough seas
associated with the first cold front will be reinforced by a new
N to NW swell through this weekend, leading to rough seas north of
20N and east of 77W. Very rough seas can be expected east of 72W
and north of 25N through Sun. Rough seas will slowly subside from
west to east Sun into next week.

$$
ERA