595
AXNT20 KNHC 220555
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0605 UTC Sun Sep 22 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
0500 UTC.

...SPECIAL FEATURES...

Potential Heavy Rainfall in Central America:
A Central American Gyre (CAG) is gradually developing over Central
America with a 1007 mb low pressure embedded along the monsoon
trough near central Panama. Scattered showers and isolated strong
thunderstorms are occurring at the southwestern Caribbean Sea near
this low. Starting early next week, it will slowly drift
northwestward across northern Costa Rica, Nicaragua, Honduras, and
the Yucatan Peninsula through the middle of next week. Aided by
abundant tropical moisture, this system may produce significant
rainfall near Panama through this weekend, then Costa Rica and
eastern Nicaragua Sunday through Tuesday. Afterward, heavy rain
may spread over central and northern Guatemala, western Honduras,
Belize and the eastern Yucatan Peninsula Monday through Thursday.
This will lead to an increased potential for life- threatening
flash flooding and mudslides in these areas. It is recommended
that residents in the aforementioned areas stay alert on the
latest information from their local meteorological agencies.
Please refer to the Tropical Weather Discussion for the Eastern
Pacific at website:
https://www.hurricanes.gov/text/MIATWDEP.shtml for rainfall across
El Salvador and the Pacific coasts of Nicaragua, Guatemala, and
southern Mexico.

...MONSOON TROUGH/ITCZ...

A monsoon trough enters the Atlantic along the coastal border of
Senegal and Guinea-Bissau, then extends southwestward across
10N28W to 08N35W. An ITCZ curves northwestward from 08N35W to
10N49W. Scattered moderate convection is seen near the trough
from 11N to 15N near the Africa coast. Similar convection is also
present up to 70 nm south of the ITCZ between 38W and 42W, and
from 08N to 11N between 44W and 50W.

The eastern end of the East Pacific monsoon trough is triggering
numerous heavy showers and scattered strong thunderstorms offshore
the border of Colombia and Venezuela.

...GULF OF MEXICO...

A modest surface ridge runs southwestward from near the Florida
Panhandle to near Tampico, Mexico. Part of a pronounced upper-
level trough stretching southwestward from southern Florida to the
northern Yucatan Peninsula is producing widely scattered showers
and thunderstorms across the Florida Strait. Gentle ENE to E winds
and seas of 1 to 2 ft are present at the southeastern Gulf and
western Bay of Campeche. Gentle to moderate E to SE winds and 2 to
4 ft seas prevail for the rest of the Gulf.

For the forecast, the ridge will dominate the Gulf into early
next week. A broad area of low pressure is forecast to form over
the northwestern Caribbean Sea and the adjacent portions of
Central America during the next few days. Thereafter, gradual
development of this system is likely, and a tropical depression
could form as the system moves slowly northwestward across the
northwestern Caribbean Sea and Gulf of Mexico through the end of
next week. There is a high chance of tropical cyclone formation in
the next seven days. Regardless of development, winds and seas
will start increasing across the southeastern Gulf early next
week.

...CARIBBEAN SEA...

Please refer to the SPECIAL FEATURES section above for potential
heavy rainfall associated with a developing Central American Gyre
(CAG).

Convergent surface winds are coupling with strong divergent flow
aloft to trigger numerous moderate to isolated strong convection
near and south of Jamaica. Scattered moderate convection is noted
farther north near the Cayman Islands and Cuba, including the
Yucatan Channel and Windward Passage. Refer to the Monsoon
Trough/ITCZ section for additional convection in the Caribbean
Sea. Moderate to locally fresh E to SE winds and seas of 3 to 5 ft
are note at the southeastern basin. Mainly moderate E to ESE winds
with 1 to 3 ft seas are found at the Gulf of Honduras. Gentle E to SE
to SW winds and seas at 1 to 3 ft exist across the southwestern
basin. Gentle to moderate E to SE winds and seas of 2 to 4 ft
prevail elsewhere in the Caribbean Sea.

For the forecast, moderate to fresh winds and moderate seas are
expected across the eastern and central basin through tonight. A
broad area of low pressure is forecast to form over the
northwestern Caribbean Sea and the adjacent portions of Central
America during the next few days. Thereafter, gradual development
of this system is likely, and a tropical depression could form as
the system moves slowly northwestward across the northwestern
Caribbean Sea and Gulf of Mexico through the end of next week.
There is a high chance of tropical cyclone formation in the next
seven days.

...ATLANTIC OCEAN...

A pronounced upper-level trough extends southwestward from the
northwestern Atlantic across 31N74W to beyond southern Florida.
Strong divergent winds related to this feature are inducing
widely scattered moderate convection from 22N to 29N between 60W
and 73W. At the central Atlantic, a surface trough meanders
eastward from 24N62W through a 1007 mb low near 26N56W to 23N44W,
then turns northeastward through another 1006 mb low near 26N42W
to 31N40W. Scattered moderate convection is found near the first
low with 60 nm of 28N55W, and the second low from 20N to 27N
between 39W and 42W. A mid-level trough near 40W is causing
scattered moderate convection from 11N to 17N between 41W and 45W.
Convergent trade winds are generating similar conditions west of
the Cabo Verde Islands from 13N to 17N between 29W and 34W. Refer
to the Monsoon Trough/ITCZ section for additional convection in
the Atlantic Basin.

Moderate to fresh E to SE winds and seas of 6 to 8 ft are evident
near the aforementioned low pressure systems from 26N to 29N
between 52W and 59W, and north of 24N between 35W and 43W.
Otherwise, gentle to locally moderate NE to SE winds with 4 to 6
ft seas are present north of 24N between 30W and the Florida-
Georgia coast. To the south from 15N to 24N between 30W and
Bahamas/Leeward Islands, light to gentle winds with seas at 2 to 4
ft exist. Farther south from the Equator to 15N between 35W and
the Windward Islands/South America coast, gentle to moderate E to
SSE winds and seas of 4 to 6 ft in mixed moderate swells are
found. Near the Canary Islands, moderate to fresh NNE to NE winds
and 5 to 7 ft seas dominate north of 18N between the northwest
Africa coast and 30W. Near the Cabo Verde Islands from 12N to 18N
between the central Africa coast and 30W, gentle to moderate NNE
to NE winds and seas at 2 to 4 ft are found. Light to gentle
southerly and monsoonal westerly winds with 4 to 7 ft seas in
mixed moderate swells prevail for the remainder of the Atlantic
Basin.

For the forecast W of 55W, a weak cold front will move off the
southeast coast of the US Sunday, then slowly move across the
waters north of 25N into Mon night.

$$

Chan