327
FXCA20 KWBC 081929
PMDCA

Tropical Discussion - International Desks
NWS Weather Prediction Center College Park MD
328 PM EDT Wed Oct 08 2025

Forecast Bulletin 8 October 2025 at 1930 UTC:

Synopsis:

A low-level induced trough in the Gulf will continue impacting the
eastern coast of Mexico, including Veracruz, San Luis Potosi, and
Tamaulipas over the next few days. This will bring significant
precipitation, and flash and urban flooding are likely to occur.
Across the Bahamas and Cuba, the development of a coastal low off
the east coast of the United States will bring heavy precipitation
and potentially severe weather late in the week into the weekend.
In the Lesser Antilles, the influence of Tropical Storm Jerry is
forecast to bring precipitation as the system progresses
northwestward, but off of the coasts of the Leeward Islands. In
Tropical South America, rainy and seasonable conditions will
continue for the next several days in the form of localized
convection.

Mexico and Central America:

The ongoing lower-level induced trough event in Veracruz, San Luis
Potosi, and Tamaulipas will continue bringing significant rainfall
to these areas today through early Friday morning. Strong
low-level winds of over 25kts with precipitable water exceeding
57mm is expected to continue flowing onshore in Veracruz, where it
will then be orographically enhanced. Additionally, the presence
of an upper level high in northern Mexico will promote strong
upper-level divergence at its eastern periphery, which will be
conducive to elevated upward ascent of air. This will continue
bringing heavy precipitation today and Thursday, before it begins
to diminish on Friday. Storm total precipitation is expected to
reach up to 200-300mm for most of Veracruz, northeast Hidalgo, and
east San Luis Potosi from today until early Saturday morning.
Locally higher amounts of over 300mm are possible in these
regions, and instances of flash and urban flooding are likely,
particularly today and Thursday.

Heavy precipitation is also expected for parts of the south coast
of Mexico, due to a developing low pressure circulation located
off the coast of Oaxaca/Guerrero. The National Hurricane is
currently monitoring this system, and has given it a 70% chance of
developing in the next two days, per the latest outlook. This
system is currently anticipated to skirt the south coast of Mexico
while remaining offshore, but will bring heavy rainfall to
Chiapas, Oaxaca, Guerrero, Michoacan, and Colima over the next few
days. Precipitation totals of up to 30-60mm are expected today and
Thursday for these areas. Further out, the system is currently
forecast to take a northwestward track, and precipitation effects
in northwest Mexico, including Jalisco, Nayarit, and Sinaloa, are
possible over the weekend.

In Costa Rica and Panama, the presence of the monsoon trough will
provide persistent onshore flow of moisture over the next few
days, bringing daily precipitation through the forecast period.
The heaviest precipitation is expected to occur on Friday, where
totals of up to 25-50mm are expected.

The Bahamas and Caribbean:

Rainy conditions in the Bahamas and Cuba will continue over the
next several days, as an upper-level trough deepens significantly
over the next few days. The trough position will result in the
Bahamas and Cuba being situated on the divergent side, and is
expected to develop a strong upper jet. This will result in strong
upper-level divergence from northern Cuba to most of the northern
Bahamas. Given this setup, a cold front currently affecting the
eastern United States is expected to progress and extend far south
into Florida and the northern Caribbean on Thursday evening. Until
then, a persistent stationary front in the Atlantic will remain in
place while gradually weakening, and is then expected to quickly
dissipate as the U.S. cold front moves south and becomes the
dominant boundary. Meanwhile, as the cold front takes its place, a
coastal low off of the east coast of the United States is expected
to begin developing on Friday. As it develops, a new cold front is
forecast to form in southern Florida/the Gulf into northern Cuba,
and is expected to bring heavy precipitation to northern Cuba and
the Bahamas. Precipitation in the Bahamas and Cuba will gradually
increase throughout the next three days as the low begins
developing early in the weekend. Additionally, there is a slight
risk of severe weather in both the Bahamas and Cuba on Friday
evening into Saturday.

In the Lesser Antilles, Tropical Storm Jerry continues to be of
great interest late in the week. The current track is expected to
remain off the coast of the northern Leeward Islands, but the
associated moisture will bring in heavy precipitation to the
Leeward Islands, Puerto Rico, and the Virgin Islands. As the storm
moves north of the Lesser Antilles, southerly flow of remnant
moisture will make its way into the northern Leeward Islands,
southern Puerto Rico, and the Virgin Islands, and precipitation
will continue after Jerrys departure. Maximum total
precipitation of up to 20-45mm and 25-50mm is expected on Thursday
and Friday respectively in the Leeward Islands. Additionally,
there is a Marginal risk of severe weather in the Leeward and
Virgin Islands.

Tropical South America:

Nothing out of the ordinary is expected for much of Tropical South
America, with precipitation expected over the next several days.
In the west coast of Colombia, a strong low-level westerly flow of
long fetch moisture is expected to enter the region on Friday and
Saturday. With weak upper-level easterly flow being present and
bringing in moisture from the Amazon, the lower-level interaction
will be conducive to high precipitation totals on the coast.

Low-level easterly moisture flow is also expected in the central
portions in South America. This moisture will converge in the
mountainous regions in northwest Brazil, Peru, Ecuador, southeast
Venezuela, and east Colombia, and will aid in the development of
daily localized convection and precipitation throughout the
forecast period.


Positions of Tropical/Easterly Waves Initialized at 12 UTC
TYP SOF INIT 09/00 09/12 10/00 10/12 11/00 11/12 12/00 12/12
TW  15N  63W   65W  67W   69W   Diss----------


For the latest available charts please visit:
https://www.wpc.ncep.noaa.gov/international/crb_day1-3.shtml

Blanco-Alcala...(WPC)
$$