720
FXCA62 TJSJ 170848
AFDSJU

Area Forecast Discussion
National Weather Service San Juan PR
448 AM AST Tue Feb 17 2026

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

.KEY MESSAGES...
Issued at 444 AM AST Tue Feb 17 2026

* Light southeasterly winds expected today, promoting warmer-than-
  normal temperatures across the islands.

* Afternoon showers and isolated thunderstorms are expected across
  interior and western Puerto Rico. Light winds will allow slow
  moving showers, increasing the potential for localized limited to
  locally elevated flooding threat.

* Marine and coastal conditions will deteriorate by Thursday with
  the arrival of another northerly swell. There is a possibility of
  new Small Craft Advisories, High Rip Current Risk statements, and
  potentially High Surf Advisories.

* Across the U.S. Virgin Islands, brief passing showers will
  continue mainly during the nighttime and early morning hours,
  along with worsening marine and beach conditions late in the
  week.

&&

.Short Term(Today through Thursday)...
Issued at 444 AM AST Tue Feb 17 2026

Fairly tranquil conditions prevailed overnight, with only a few
showers developing over the surrounding waters. This pattern will
persist through the morning hours, with early activity remaining
brief and mainly affecting localized windward coastal areas of
Puerto Rico and the smaller islands.

Today, the region remains under the influence of a surface col north
of the forecast area, situated ahead of an approaching pre-frontal
trough. Additionally, cooler 500 mb temperatures and a 60-70 kt
upper-level jet over the northeastern Caribbean will enhance upper-
level divergence and provide additional instability. Low-level winds
will remain light and temperatures warmer than normal, allowing sea
breeze convergence and local effects to dominate. With near-seasonal
moisture in place, diurnal heating will promote scattered showers
and isolated thunderstorms during the afternoon, mainly across
interior and western Puerto Rico.

Due to weak steering flow, slow-moving showers may produce locally
enhanced rainfall accumulations. Therefore, a limited but localized
elevated flooding threat is expected across interior and western
Puerto Rico.

Tonight into Wednesday, morning showers will again favor windward
areas followed by afternoon convection across interior and western
Puerto Rico. The upper-level jet will gradually shift eastward and
begin exiting the northeastern Caribbean by late Wednesday. Although
isolated thunderstorms remain possible, activity should become
somewhat more localized late in the day.

By Thursday, mid-level ridging builds over the region behind the
departing jet while precipitable water values fall below normal. The
resulting drier and more stable air mass will promote mostly fair
weather conditions, limiting convection to isolated afternoon
showers over western Puerto Rico and brief trade-wind showers across
eastern areas.

&&

.Long Term(Friday through Tuesday)...
Issued at 444 AM AST Tue Feb 17 2026

Mostly stable conditions on the upcoming weekend and early next
week, with slight uncertainty by the end of the forecast period. The
wind pattern transition is expected on Sunday, from the east to the
southeast, as the surface high pressure migrates from the western
Atlantic into the Central Atlantic. Drier air masses will filter
into the region for most of the period, with occasional patches of
moisture that will increase shower activity. Theres a medium chance
of seasonal to below normal PWAT values (1.0 - 1.2 inches, up to 1.4
inches with the arrival of the patches), based on the probabilistic
guidance of the GFS and ECMWF. Additionally, ensemble members
continue to show low variability (approximately 0.2 inches),
increasing confidence. As mentioned in the previous discussion,  a
mid-level ridge is expected to move over the Bahamas and linger
during the weekend, with warmer-than-normal mid-level temperatures
(500 mb temperatures up to 4 degrees Celsius), sinking air, and
stability aloft. Under a blocking pattern, shower activity should
remain limited and shallow. Hence, the most likely scenario is
shower activity over the waters moving into windward sections during
the night into the morning hours, with afternoon convection over
interior and western/northwestern Puerto Rico, including streamers
from the U.S. Virgin Islands. Due strengthening winds, showers
should move quickly, with a low chance of significant rainfall
accumulations. Hence, the flood and lightning threat should remain
low. Theres a model discrepancy regarding Tuesday`s weather
conditions, as both GFS and ECMWF suggest a deep-layered trough that
may deepen into the tropics and introduce instability. Nevertheless,
theres variability in terms of moisture content (PWAT difference up
to 0.4 - 0.5 inches). Hence, uncertainty remains high for the end of
the forecast period.

As mentioned in the previous discussion, slightly warmer-than-normal
temperatures are still expected throughout the forecast period.
Although theres a low chance of heat indices exceeding 100 degrees
Fahrenheit, maximum temperatures may reach the low 90s in localized
urban and coastal areas across the islands.

&&

.AVIATION...
(06Z TAFS)
Issued at 444 AM AST Tue Feb 17 2026

Mainly VFR conds expected at all terminals through the period. Brief
MVFR possible aft 17/17z at TJBQ/TJPS due to vcty SHRA/-TSRA with
mtn obscurations across interior PR and SHRA/isol TSRA en route.
VCSH possible at TJSJ/TIST/TISX at times. Light SE sfc winds bcm sea-
breeze driven, generally blo 10 kt, with afternoon variations. The
16/00Z TJSJ sndg indicated SE winds up to 8 kt blo FL100.

&&

.MARINE...
Issued at 444 AM AST Tue Feb 17 2026

A surface high pressure over the Central Atlantic, a frontal low
moving into the central Atlantic and a weak front and associated pre-
frontal trough moving mainly north of the region will promote light
southeasterly winds to start the day. As another surface high moves
into the western Atlantic and a col moves north of the area, winds
will back to become more easterly late this afternoon into tomorrow,
Wednesday. Hazardous seas, around 7 feet, are expected on Thursday
through early Saturday due to the arrival of a long-period northerly
swell.

&&

.BEACH FORECAST...
Issued at 444 AM AST Tue Feb 17 2026

North facing beaches of Puerto Rico, and Culebra, are under a
moderate risk of rip currents (life-threatening rip currents are
possible in the surf zone) through late this afternoon becoming a
low risk tonight through early Wednesday. Other beaches of the
islands will have a low risk of rip currents from this morning
through early Wednesday. Even if the risk for rip currents is low,
life-threatening rip currents often occur in the vicinity of groins,
jetties, reefs, and piers.

Beach conditions will quickly deteriorate during the second half of
the week. A long period northerly swell, around 7 feet at 13 seconds
will promote a the moderate risk late Wednesday and a high risk
(life-threatening rip currents are likely in the surf zone) from
Thursday and into the weekend across all northern beaches of PR
(including Vieques and Culebra) and the northern USVI. Therefore,
life-threatening rip currents and high surf conditions can be
expected during the second part of the week. Visit
weather.gov/beach/sju for the latest information.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...None.
VI...None.
AM...None.
&&

$$

SHORT TERM, AVIATION, KEY MESSAGES...CVB
LONG TERM....MNG
MARINE/BEACH...MRR

NWS SJU Office Area Forecast Discussion