RSS NHC Tropical Weather Discussion

NHC Atlantic Tropical Weather Discussion

000
AXNT20 KNHC 182142
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0015 UTC Sun Oct 19 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
2130 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 generate rough to very rough seas over the western
Atlantic through this weekend. Seas in excess of 12 ft and
greater, with period of 12-14 seconds will continue to spread
southeastward today, covering the waters north of 25N between 43W
and 70W by tonight. 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 today.

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 its axis near 22W from
from 02N to 15N moving westward around 10 kt. Scattered moderate
convection is noted from 08N to 11N between 21W and 24W.

A central Atlantic tropical wave has its axis near 37W from 02N
to 10N, moving westward at 10 to 15 kt. No significant convection
is evident near this tropical wave.

An Atlantic tropical wave has its axis near 51W from 04N to 18N,
moving westward at 15-20 kt. A scatterometer satellite pass from
13 UTC indicated the system lacks a closed circulation, but strong
to near-gale force winds were observed along a sharp surface
trough along the wave axis, mainly from 12N to 15N. A concurrent
Sentinel-3B altimeter pass confirmed seas of at least 8-9 ft near
the core of strongest winds. Invest AL98 has been opened to
monitor this wave. Environmental conditions appear marginally
conductive for slow development over the next couple of days as
the system moves quickly westward at 20 kt, crossing the Windward
Islands and entering the Caribbean Sea by early next week. By the
middle of next week, the system is expected to slow down over the
central Caribbean Sea, where environmental conditions could become
more favorable for further development. Regardless of
development, this system is expected to bring heavy rainfall and
gusty winds to the Windward Islands Sun and Sun night.

An Atlantic tropical wave has its axis near 59W south of 16N, moving
westward near 15 kt. A scatterometer satellite pass from 1330 UTC
indicated fresh to strong winds near the wave axis from 10N to
12N. Numerous moderate to isolated strong convection is noted
from 06N to 13N between 56W and 62W.

...MONSOON TROUGH/ITCZ...

The monsoon trough enters the Atlantic near 13N16W and extends
southwestward to near 05N30W. Segments of the ITCZ extend from
05N30W to 05N36W, and from 05N40W to 03N50W. Other than the
convection discussed in the Tropical Waves section above, no
significant convection is ongoing along the monsoon trough and
ITCZ at this time.

...GULF OF AMERICA...

A few showers and thunderstorms are active off the central
Louisiana coast, south of a coastal trough reaching from off
Morgan City, Louisiana to off Port Connor, Texas. 1020 mb high
pressure is centered off Cape Hatteras, NC. South of the high
pressure, a plume of moderate E to SE winds with 4 to 5 ft seas
extends from the Straits of Florida to near the mouth of the
Mississippi River. The moist, convergent flow is supporting the
showers and thunderstorms off Louisiana. Light to gentle breezes
with 1 to 3 ft seas are noted elsewhere.

For the forecast, locally fresh S to SE winds will occur into Sun
east of 90W, including through the Florida Straits, as high
pressure builds over the western Atlantic. A cold front will move
into the northwestern Gulf Sun morning and move southeastward over
the basin through Mon. Moderate N to NE winds are expected north
of the cold front, and locally fresh winds will be possible north
of 26N into Mon morning. High pressure is slated to develop over
the basin in the wake of the front, leading to gentle to moderate
winds and slight seas over the Gulf early next week.

...CARIBBEAN SEA...

Convergent easterly flow and lingering moisture from an old trough
are supporting scattered showers and thunderstorms across the
northwest Caribbean this morning, mainly north of 18N. Convergent
trade wind flow is also supporting a few showers and thunderstorms
across the far southwest Caribbean between Panama and Nicaragua.
Farther east, an upper trough is supporting a few showers and
thunderstorms across the south-central Caribbean off northeast
Colombia and northwest Venezuela. Scattered showers and thunderstorms
are impacting southern Windward Islands from St Vincent to Grenada,
ahead of the approaching tropical waves. Clusters of these
thunderstorms are training in lines from east to west, and could
bring heavy rainfall to these islands. Moderate SE winds and 2 to
4 ft seas are noted over the eastern Caribbean, and gentle E to
SE breezes and 1 to 3 ft seas are noted elsewhere.

For the forecast, moderate to fresh E winds and moderate seas are
expected over the south-central and eastern basin tonight through
Sun as high pressure builds over the western Atlantic. Locally
strong winds will be possible in the Gulf of Venezuela on Sun. A
long period N swell will lead to rough seas through the Atlantic
passages and over the waters east of the Lesser Antilles Sun into
early next week. Looking ahead, a tropical wave located in the
central Atlantic will move westward this weekend, entering the
eastern Caribbean Sun night. Environmental conditions appear
marginally conductive for slow development over the next couple of
days. By the middle of next week, the system is expected to slow
down over the central Caribbean Sea, where environmental
conditions could become more favorable for further development.
Regardless of development, fresh to strong winds and rough seas
will accompany this wave as it moves over the eastern and central
Caribbean early next week. This system has a low chance of
tropical development within the next 7 days.

...ATLANTIC OCEAN...

Please refer to the Special Features section for further details
on a large swell event that will impact some sections of the
north-central waters through the weekend, and details about the
tropical wave/Invest AL98W near 50W.

A cold front extends from 31N48W to southern Bahamas and Turks
and Caicos Islands, west of 1021 mb high pressure near 27N37W.
Scattered showers and thunderstorms are active within 150 nm east
of the front. Fresh to strong W to NW winds are west of the front
to 65W, north of 25N. Fresh to strong SW winds are also evident
within 240 nm east of the front, north of 25N. Seas are in excess
of 8 ft north of 23N between 40W and 75W. Outside of the area of
winds and seas associated with Invest AL98 described in the
Special Features section, moderate to fresh NE to E trade winds
and 5 to 7 ft seas are noted south of 20N, with gentle to moderate
breezes and 4 to 6 ft seas elsewhere.

For the forecast W of 55W, the front will progress northeastward
this weekend. Fresh to strong W to NW winds are expected in the
wake of the front north of 27N and east of 65W through Sun
morning. Widespread rough seas associated with this storm system
will continue north of 20N and east of 77W through tonight, with
rough seas expanding southeastward through the Greater Antilles
Atlantic Passages on Sun. Very rough seas in excess of 12 ft are
expected north of 25N and east of 72W through Sun afternoon. Rough
seas will slowly subside from west to east Sun into early next
week. Elsewhere, moderate to locally fresh E to NE winds will
occur over the Bahamas and through the Florida Straits through Sun
morning as high pressure builds over the western Atlantic this
weekend. Looking ahead, a series of cold fronts are slated to push
off the coast of the southeastern United States early next week,
leading to increasing N winds offshore of Florida.

$$
Christensen