508
FXCA20 KWBC 031959
PMDCA

Tropical Discussion - International Desks
NWS Weather Prediction Center College Park MD
259 PM EST Mon Nov 03 2025

Forecast Bulletin 03 November 2025 at 2000 UTC:

Mexico, Central America, and the Caribbean:

An Easterly wave is situated over the southwest Caribbean sea, at
around 79W, and is expected to propagate westward into the
Atlantic coast of Costa Rica and Nicaragua tonight into early on
Tuesday morning. In the mid-levels, an inverted trough,
substantial cyclonic vorticity, and strong mid- to upper-level
divergence will aid in the ascent of unstable air, while in the
lower levels, high levels of precipitable water, in excess of
60mm, are expected to flow from the east onshore in the Atlantic
coastal region of Costa Rica and Nicaragua today into tomorrow.
With this, and orographic enhancement, heavy precipitation will
occur, with a maximum of 35-70mm expected today in Costa Rica.
Precipitation is also expected in east Nicaragua today and tonight
as the wave progresses westward, however, given weakened
orographic and local effects due to lower mountaintops in the east
side of Nicaragua, precipitation will be lighter, with totals up
to 20-35mm expected, with locally higher amounts are possible. The
northern coast of Honduras will also receive heavy precipitation
due to northerly onshore flow of moisture associated with the wave
today into Tuesday morning. A maximum of 50-100mm is expected for
northern Honduras, with the heaviest precipitation occurring in
the overnight/early morning hours on Tuesday.

On Tuesday, the wave will continue propagating westward, while an
associated low-level trough separates from the wave and propagates
northwestward, reaching the east coast of Belize and the Yucatan
Peninsula in Mexico. Northerly onshore flow is expected to
continue in the northwest coast of Honduras, to include the Gulf
of Honduras, and northeasterly onshore flow is anticipated to
commence in Belize and the east coast of the Yucatan Peninsula on
Tuesday. There will be less moisture available during this time,
and most precipitation will be much more localized. The heaviest
precipitation on Tuesday is forecast to occur in the Gulf of
Honduras in the afternoon, with 20-45mm expected.

Meanwhile in Cuba and the northern Yucatan Peninsula, a deep
positively tilted upper-level trough in the continental United
States is expected to extend from Florida, the Gulf, into the
Yucatan Peninsula today and remaining on Tuesday. A cold front
associated with it, currently extending from the central Bahamas,
northwest Cuba, and just north of the Yucatan Peninsula, will
continue progressing southeastward over the next three days. While
the previously mentioned Caribbean mid-level trough continues to
progress northwestward into the Yucatan on Tuesday, it will also
meet and interact with the cold front on Tuesday. The position of
the U.S. upper-level trough will aid in upper level divergence in
northwest Cuba on Tuesday, and with the additional interaction
with the Caribbean mid-level trough, a marginal risk of severe
weather is possible on Tuesday into Wednesday for northwest Cuba.
In the northeast Yucatan Peninsula, precipitation up to 20-35mm is
expected on Tuesday. On Wednesday, precipitation in the northern
Yucatan Peninsula will reach a maximum of 15-25mm.

In the south coast of Costa Rica and Panama, the presence of the
monsoon trough will aid in the westerly flow of moisture, which
will bring daily seasonable precipitation for the next two days,
before diminishing on Thursday. The heaviest precipitation will
occur today, with 20-45mm expected in the south coast of Costa
Rica, and 20-35mm expected in Panama. By Thursday morning, the
low-level wind regime will shift from a west-southwest onshore
flow, to a northerly offshore flow, which will aid in diminishing
precipitation totals in Panama and Costa Rica.

Tropical South America:

In the interior regions of tropical South America, precipitation
will continue to be caused by local, diurnal, and orographic
effects. Moisture flowing westward from the Amazon will continue
to provide fuel for daily convection in northwest Brazil, Ecuador,
and northeast Peru for the next three days. In west Colombia,
moisture associated with the monsoon trough, along with westerly
low-level flow will yield heavy precipitation for the next three
days, with the heaviest precipitation occurring on Tuesday and
Wednesday. In the northeast region of South America, a plume of
moisture associated with an easterly wave is expected to propagate
westward through northwest Guyana, east Venezuela, and Trinidad
and Tobago today and Tuesday, and precipitation totals up to
15-25mm are expected.



Positions of Tropical/Easterly Waves Initialized at 12 UTC
TYP SOF  INIT  04/00  04/12  05/00  05/12  06/00  06/12  07/00
EW  12N   59W   60W    62W    64W    66W    68W    70W    72W
EW  15N   78W   80W    82W    84W    86W    88W    90W    92W

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

Blanco-Alcala...(WPC)
$$