824
FXCA62 TJSJ 021840
AFDSJU

Area Forecast Discussion
National Weather Service San Juan PR
240 PM AST Sun Nov 2 2025

...New SHORT TERM, AVIATION, MARINE, BEACH FORECAST...

.KEY MESSAGES...
Issued at 237 PM AST Sun Nov 2 2025

* Mostly dry and hazy conditions will prevail through this evening
  as a stable and drier air mass continues to dominate the region.

* Increasing moisture is expected late tonight into Monday as a
  trade wind perturbation approaches. Quick-moving showers and
  isolated thunderstorms on Monday may lead to minor ponding of
  water in poor-drainage areas, but widespread flooding is not
  anticipated.

* Another drier air mass is forecast to move in by early Tuesday,
  promoting mostly fair weather with limited shallow afternoon
  convection.

* Across the U.S. Virgin Islands, mainly fair weather will prevail,
  with passing showers increasing late tonight into Monday as
  moisture increases.

* Breezy easterly winds will continue through early week,
  maintaining choppy seas and a moderate risk of rip currents for
  most local beaches.

&&

.Short Term(This evening through Tuesday)...
Issued at 237 PM AST Sun Nov 2 2025

This morning was fairly tranquil across the local islands with
mostly clear to partly cloudy skies, the result of a more stable
airmass settling over the region. The 02/12Z TJSJ sounding indicated
reduced precipitable water (PWAT) values near 1.68 inches, along
with mid-level relative humidity around 42%, consistent with a drier
and more stable profile. Surface observations reported breezy
conditions, particularly across coastal areas, where wind gusts
reached the lower to mid-20s mph range. Additionally, traces of
Saharan dust led to hazy skies, while heat index values exceeded
100F across several urban and coastal sectors, though the overall
heat risk remained mostly limited.

For the remainder of the afternoon and into the evening hours,
mostly fair weather conditions will persist. The Advected Layer
Precipitable Water (ALPW) analysis highlights a notably dryer layer
between 700-500 mb moving across the region. These factors will
further suppress shower development, maintaining limited convective
potential through the evening. Only brief, isolated light showers
may develop over the local waters or windward slopes, but
significant rainfall is not expected.

Conditions will gradually become wetter starting late tonight into
Monday as a trade wind perturbation approaches from the east. This
feature will bring increasing PWAT values to near or slightly above
climatological normal. Expect higher cloud coverage and more
frequent passing showers during the early morning hours, especially
across windward and coastal areas.

By Monday afternoon, diurnal heating, sea breeze convergence, and
local effects over Puerto Ricos interior and western sectors will
enhance shower and isolated thunderstorm development. Model guidance
indicates sufficient low-level moisture to sustain convection and
some instability; however, ridging aloft will persist, with
subsidence maintaining warmer-than-normal 500 mb temperatures.
Moderate steering winds will promote quick-moving showers and
thunderstorms, limiting rainfall accumulations. Localized ponding or
minor flooding cannot be ruled out.

By early Tuesday, another dry slot is expected to move in behind the
perturbation, leading to a return of mostly fair and stable weather
for the rest of the day. Shallow afternoon showers will remain
possible due to local effects, but no significant rainfall or
flooding threat is expected.

&&

.Long Term(Wednesday through next Saturday)...
Issued at 500 AM AST Sun Nov 2 2025

Based on the latest model guidance, the wind pattern will be
primarily influenced by a strong high-pressure system over the
central Atlantic, promoting winds with an easterly component
through most of the period. Aloft, a mid-level ridge is expected
to persist north of the region, maintaining stable and relatively
dry conditions. However, an upper-level low moving south of the
area, over the Caribbean waters, will slightly weaken atmospheric
stability and induce weak surface troughs.

Precipitable water (PWAT) guidance indicates that moisture content
will fluctuate between near to below normal levels for much of the
period, with patches of low-level moisture periodically moving
into Puerto Rico and the U.S. Virgin Islands. As a result, there
will be a low to medium chance (2040%) of brief passing showers
across the windward portions of the U.S. Virgin Islands and
eastern Puerto Rico during the morning hours, followed by
afternoon convection over western Puerto Rico (5060%) driven by
local effects, available moisture, and marginal instability
through Friday. During this time, the flood threat remains
limited, with ponding of water on roads and in poorly drained
areas possible. By Saturday and Sunday, a tropical wave is
expected to increase moisture and wind speeds across the eastern
Caribbean, resulting in a higher chance of showers and a potential
increase in flood risk. Additionally, a limited heat risk is
likely to persist.

&&

.AVIATION...
(18Z TAFS)
Issued at 237 PM AST Sun Nov 2 2025

VFR conds will prevail across all terminals through the period.
Brief -SHRA may affect the VCTY of TJSJ, TIST, and TISX aft 03/06Z
with passing trade wind showers. HZ will persist due to suspended
Saharan dust, but VIS will remain above 6SM. EESE winds 1015 kt
with higher gusts, becoming more E overnight and into Mon. SHRA/TSRA
may develop across interior and W PR aft 03/17Z, possibly affecting
the VCTY of TJBQ/TJPS.

&&

.MARINE...
Issued at 237 PM AST Sun Nov 2 2025

A surface high pressure over the central Atlantic will promote
moderate to locally fresh trade winds through early this workweek.
Wind-driven, choppy to hazardous seas will prevail through this
evening, particularly across the offshore Atlantic and Caribbean
waters, and Mona Passage, where Small Craft Advisories are in
effect. Seas improving from this evening onward and winds are
forecast gradually become lighter around Monday night onward.

&&

.BEACH FORECAST...
Issued at 237 PM AST Sun Nov 2 2025

Moderate rip currents persist across most beaches of Puerto Rico and
the U.S. Virgin Islands, especially along north- and east-facing
coasts. These conditions are expected to continue for the next few
days as breezy easterly winds maintain choppy seas. Gradual
improvement is anticipated by midweek, although a moderate risk may
linger along the northern beaches of Puerto Rico and Culebra.
Beachgoers should remain cautious, as hazardous rip currents are
still possible near the surf zone. For additional updates, visit
weather.gov/beach.&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...None.
VI...None.
AM...Small Craft Advisory until 6 PM AST this evening for AMZ733-741.

&&

$$

.MORNING CREW...CVB/RVT