443
FXCA62 TJSJ 210954 CCA
AFDSJU
Area Forecast Discussion...CORRECTED
National Weather Service San Juan PR
554 AM AST Fri Nov 21 2025
...New SHORT TERM, LONG TERM, AVIATION, MARINE, BEACH FORECAST...
.KEY MESSAGES...
Issued at 423 AM AST Fri Nov 21 2025
* Pleasant temperatures will prevail across the USVI and PR from
today through early next week.
* One or two thunderstorms will form this afternoon, especially
near the southwest quadrant of PR.
* The north- and east-facing beaches of PR and the USVI will have
a moderate risk of rip currents through Saturday evening, then
drop to low from Sunday through Tuesday.
&&
.Short Term(Today through Sunday)...
Issued at 423 AM AST Fri Nov 21 2025
A passing trough aloft, lingering moisture, and cooler northeast
winds helped showers develop overnight and drift southwest across
the local waters. Radar showed scattered showers mainly over the
Atlantic, with some of this activity moving into northern and
eastern Puerto Rico, Culebra, and the northern United States Virgin
Islands. Since last evening, around one half inch of rain fell in an
isolated spot in northeastern Puerto Rico. Overnight temperatures
dropped into the mid 70s across lower elevations and the low 60s in
the mountains, with a few upper 50s near Jayuya. These colder
readings provided an early hint of the anticipated episode of
Friiito Navideno. Winds over land were light and variable through
the night.
A persistent moderate northeast breeze will continue to bring
passing trade wind showers throughout the day, although they will be
more frequent early this morning. A shortwave trough moving across
the area will keep slightly cooler air aloft through early
afternoon, supporting a few afternoon showers and isolated
thunderstorms, mainly over southwestern Puerto Rico. Drier air will
begin filtering in later this afternoon and will quickly shut down
most activity. Highs will be slightly cooler than recent days,
reaching the low to mid 80s across coastal and urban areas, further
signaling the Friito Navideno expected to persist through at
least Saturday. Today is the only period with any meaningful
weather risk, with isolated lightning and minor flooding possible
in afternoon storms.
Much drier and more stable air will move in as high pressure builds
from the west, sharply reducing shower and thunderstorm activity
tonight through Sunday. Saturday will be mostly dry with little to
no rainfall expected. On Sunday, slightly patchier moisture may
bring a few additional showers to windward areas, drifting inland at
times and allowing for scattered showers to develop in the
afternoon, but rainfall amounts will remain low. Temperatures will
continue a cooling trend, with highs likely in the low 80s and some
higher terrain barely warming to around 70 degrees. Lows may dip
into the mid 50s in the highest elevations during clearer nights.
Weather related risks will remain minimal through the weekend.
&&
.Long Term(Monday through Friday)...
Issued at 423 AM AST Fri Nov 21 2025
Model guidance is trending toward greater consensus, suggesting a
potential climatological pattern across the Northeast Caribbean,
including Puerto Rico and the US Virgin Islands. However, a short-
wave trough aloft will swing by the region from the west,
increasing the potential for afternoon convection (30-50 percent
chance of precipitation), especially around Monday afternoon into
the evening along the Cordillera Central and crossing the USVI.
From Tuesday into Thursday, there is a better agreement that high
pressure at mid levels will promote subsidence and a trade wind
inversion over the region, trapping all the moisture at low
levels. Thus, we expect a mixture of sunshine and clouds, with
occasional patches of moisture embedded in the trades bringing
showery weather over the windward locations of PR and the USVI.
However, this activity does not represent a flooding threat for
the region.
Temperatures across the islands are expected to continue cooling.
Model forecasts suggest that temperatures at 925 mb will be
slightly below normal, roughly at the 25th percentile compared to
typical November conditions. However, there may be instances,
particularly during peak heating in the afternoon, when
temperatures can reach near-normal levels (around the 50th
percentile).
&&
.AVIATION...
(06Z TAFS)
Issued at 423 AM AST Fri Nov 21 2025
Mostly VFR thru the prd with very ltd SHRA/TSRA. VCSH at TJSJ/USVI
tmnls thru 21/14Z and again aft 21/23Z. Brief VCTS psbl nr TJPS
21/1720Z. Isold brief MVFR psbl due to MTN OBSC/REDUCED VIS, but
confidence remains low. SFC winds LGT/CALM/VRB early, bcmg NE 1014
kt aft 21/14Z, with local S/B influences at TJBQ/TJPS causing VRB or
onshore flow at times, then rtnng LGT/VRB aft sunset. Gen steering
flow NE.
&&
.MARINE...
Issued at 423 AM AST Fri Nov 21 2025
A surface high pressure will build over the western Atlantic
during the next few days, promoting moderate to fresh trade winds
from late tonight into the weekend. A surface low over the eastern
Atlantic will generate pulses of long period northeasterly swells,
arriving around Tuesday or Wednesday of next week. Afternoon
thunderstorms will form across southwestern Puerto Rico today.
&&
.BEACH FORECAST...
Issued at 423 AM AST Fri Nov 21 2025
A moderate risk of rip currents will prevail for the north and
east-facing beaches in PR and the USVI through at least late
Saturday night. The risk is forecast to be low from Sunday to
Tuesday evening. Then, another long-period northeasterly swell
will increase the risk to moderate or high from late Tuesday night
into the middle of next week.
Additionally, beachgoers should be aware of other potential
hazards, such as lightning and gusty winds, due to showers and
thunderstorm activity expected this afternoon, especially near the
southwest coast of PR. Remember: If thunder roars, go indoors!
&&
.SJU WATCHES/WARNINGS/ADVISORIES...
PR...None.
VI...None.
AM...None.
&&
$$
SHORT TERM/AVIATION...ICP
KEY MESSAGES/LONG TERM/MARINE/BEACH FORECAST....CAM
NWS SJU Office Area Forecast Discussion