820
AXNT20 KNHC 180423
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0605 UTC Wed Sep 18 2024

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 0000 UTC surface analysis and satellite imagery through
0355 UTC.

...SPECIAL FEATURES...

Central Atlantic Ocean Significant Swell Event: A 1007 mb non-
tropical low pressure center is near 28N51W. A cold front extends
from the low center to 23N55W, followed by a stationary front to
31N64W. A warm front extends form the low center to 27N46W,
followed by a stationary front to 31N37W. Strong to near gale NE
to E winds and seas of 12 ft and greater are occurring within 180
NM to the west and north of the center. Peak seas are around 16
ft. Numerous moderate and scattered strong convection is noted
north of 26N and east of the center to 42W. The system will
gradually weaken as it moves slowly toward the southwest Wed and
Thu. Winds will diminish below strong force and seas below 12 ft
by Thu night.

Please see 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...

An eastern Atlantic tropical wave is along 29W, south of 20N,
moving westward at 5 kt. A few showers are found near the trough
axis.

A central Caribbean tropical wave is along 79W, south of 20N,
moving westward at 5-10 kt. A few showers and isolated
thunderstorms are seen near the trough axis, especially along the
northern portion.

...MONSOON TROUGH/ITCZ...

The monsoon trough reaches the Atlantic near 15N17W through the
coast of Senegal and continues west-southwestward to 12N29W and
then to 15N43W. Isolated to scattered moderate convection is
present from 05N to 15N and east of 31W.

...GULF OF MEXICO...

Generally dry conditions are prevalent over much of the Gulf of
Mexico. A few showers and isolated thunderstorms are evident in
the eastern Bay of Campeche as storms that formed over western
Yucatan earlier tonight move westward. A persistent weak pressure
gradient across the Gulf supports moderate or weaker winds and
slight seas.

For the forecast, weak surface ridging over the Gulf waters will
support generally light to gentle winds and slight seas through
Thu. Moderate to locally fresh winds may pulse in the Bay of
Campeche nightly through Fri. A cold front moving through the NE
Gulf will lead to moderate NE winds across the basin on Fri, and
building high pressure this weekend will support a gentle to
moderate anticyclonic flow.

...CARIBBEAN SEA...

A sharp upper level trough over the SE United States continues to
enhance the development of showers and isolated thunderstorms
over the NW Caribbean, with the strongest activity affecting Cuba
and surrounding waters. A few showers are also seen in the eastern
Caribbean. A broad ridge to the north of the islands forces
moderate to fresh easterly winds and seas of 4-7 ft across the
central Caribbean and Gulf of Honduras. Elsewhere, moderate or
weaker winds and slight to moderate seas prevail.

For the forecast, the pressure gradient between high pressure centered
near 26N68W and the Colombian low will continue to support
moderate to fresh trades and moderate seas across the central
Caribbean through Wed. Locally strong winds and rough seas will be
possible off the coast of Venezuela and Colombia. For Thu through
the weekend, moderate trades and slight seas will occur across
the central Caribbean, with light to gentle winds occurring across
northwest and southwest portions of the basin. Moderate to
locally fresh winds may pulse in the Gulf of Honduras nightly
through Fri.

...ATLANTIC OCEAN...

Please read the Special Features section for details about the
Central Atlantic Ocean Significant Swell Event.

A sharp upper level trough over the SE United States and abundant
moisture continues to support scattered showers and isolated
thunderstorms west of 68W and north of 24N. Similar convection is
also noted between Cuba and the central Bahamas. The rest of the
SW North Atlantic, west of 55W, is under the influence of a broad
subtropical ridge located in the NW Atlantic. This ridge forces
fresh to strong easterly trade winds south of 22N and between 69W
and 73W. This was confirmed by a recent scatterometer satellite
pass. Seas in these waters are 4-6 ft. Elsewhere west of 55W
outside of the influence of the low pres near 28N51W, moderate or
weaker winds and moderate seas prevail.

A broad area of low pressure centered near 20N49W, the remnants
of Gordon, is producing disorganized showers and thunderstorms,
mainly south of the center. A surface trough extends from the low
center to the Windward Islands and scattered showers are observed
near this boundary. Moderate to locally fresh southerly winds and
seas of 5-7 ft are occurring from 15N to 24N and between 44W and
50W. The broad subtropical ridge dominates the remainder of the
tropical Atlantic, sustaining moderate or weaker winds and
moderate seas.

For the forecast, a non-tropical low pressure system located near
28N51W will lead to strong to near gale force winds north and
west of the center of the low pressure, generally north of 27N
and east of 58W through Thu. Rough seas are expected east of 60W
and north of 23W, with peak seas of 8 to 12 ft in NE swell. These
marine conditions will gradually diminish on Fri. Expect pulsing
fresh trades off the coast of Hispaniola through Thu. Otherwise,
gentle to moderate winds and slight to moderate seas will
prevail across the rest of the basin.

$$
Delgado