230
FXCA62 TJSJ 080754
AFDSJU

Area Forecast Discussion
National Weather Service San Juan PR
354 AM AST Fri May 8 2026

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

.KEY MESSAGES...
Updated at 339 AM AST Fri May 8 2026

* Warm to hot weather will continue through the middle of next
  week, particularly in urban and coastal areas of Puerto Rico and
  the U.S. Virgin Islands.

* Locally induced afternoon showers are expected to develop each
  afternoon over portions of western Puerto Rico.

* Across the USVI, mostly fair weather conditions are expected.
  Passing trade wind showers cannot be ruled out at times.

* A moderate rip current risk will prevail for the north- and
  east-facing beaches of Puerto Rico, Culebra, Vieques, and the
  U.S. Virgin Islands through the weekend.

&&

.Short Term(Today through Sunday)...
Issued at 339 AM AST Fri May 8 2026

A mid-level ridge building over the northeastern Caribbean will
maintain a predominantly stable and dry weather pattern through
the weekend. The GFS indicates that while low-level moisture
remains present, a significant dry layer between 700-500mb (with
RH values dropping below 30%) and warmer 500mb temperatures up to
4 degrees C will provide strong subsidence and entrainment. This
will limit vertical development and the potential for deep
convection compared to yesterday. Total precipitable water (PWAT)
values are forecast to range between 1.20 and 1.50 inches, which
is on the lower end of the climatological normal (near the 25th
percentile) for early May, further supporting limited rainfall
activity.

Having said that, a surface high pressure north of the region will
promote breeze trades around 15-20 knots. This flow will steer
occasional shallow moisture patches across the islands, bringing
brief, fast-moving showers to windward sections of the USVI and
eastern Puerto Rico during the overnight and early morning hours.
Diurnal heating and sea breeze convergence will trigger isolated
afternoon showers over the interior and western sections of Puerto
Rico. Hi-res NBM guidance suggests that daily accumulations will
generally remain below half an inch, with only highly localized
amounts exceeding that.

The primary concern through Sunday will be the persistent heat
risk. With 925mb temperatures remaining above normal (reaching
21-22C) and surface highs nearing 90F in coastal and urban areas,
heat indices are expected to exceed 100F.

&&

.Long Term(Monday through Friday)...
Issued at 339 AM AST Fri May 8 2026

A generally drier-than-normal pattern for shower development will
persist through the period as mid-level ridging and subsidence
dominate across the region. Moisture will remain below normal for
this time of year and mostly confined below 700750 mb, limiting
vertical growth and resulting in reduced shower activity. An east to
east-southeasterly steering flow will prevail, supporting a
consistent daily pattern with brief, quick-moving passing showers
affecting windward areas during the overnight and morning hours,
followed by isolated afternoon convection over interior to west-
northwestern Puerto Rico, driven by local effects and mostly diurnal
heating. Isolated thunderstorms cannot be ruled out, but coverage
will remain very limited. Minor traces of Saharan dust may be
present at times, though concentrations are expected to remain low.

Breezy conditions will increase into the weekend and early next
week, particularly across coastal and windward areas, supporting a
limited non-thunderstorm wind risk with occasional gusts up to
around 25 mph or higher at times. Increasing temperatures combined
with warm and humid low-level conditions will promote a limited heat
risk each day, mainly affecting sensitive individuals or those with
prolonged outdoor exposure and inadequate hydration. In addition,
the combination of warm temperatures and increasing winds will
maintain the potential for elevated fire danger, particularly across
southern and coastal areas where fuels will continue to dry.

&&

.AVIATION...
(06Z TAFS)
Issued at 339 AM AST Fri May 8 2026

Mainly VFR conditions are expected to prevail across all terminals
during the next 24 hours. However, iso -TSRA could develop over
the SW quadrant of PR this afternoon, which may cause VCTS at
TJPS. Mostly VCSH expected elsewhere. Winds ENE at 15-20 kt

&&

.MARINE...
Issued at 339 AM AST Fri May 8 2026

A strengthening surface high pressure over the western Atlantic will
promote moderate to locally fresh east-to-northeast winds across the
regional waters. Therefore, expect choppy marine conditions due to
increasing winds. Breezy trade winds will persist into early next
week, with occasional winds reaching up to 20 knots. Small craft
are urged to exercise caution across portions of the local waters.


&&

.BEACH FORECAST...
Issued at 339 AM AST Fri May 8 2026

There is a low risk of rip currents across all beaches in PR and
the USVI. Nonetheless, life-threatening rip currents often occur
in the vicinity of groins, jetties, reefs, and piers. Beachgoers
are encouraged to exercise caution while enjoying the north-and
east-facing beaches from Rincon to Fajardo, as well as the
northern shores of Culebra and Vieques. Where, locally stronger
rip currents are possible.

Increasing winds will promote a moderate risk of rip currents across
most of Puerto Rico, and the USVI by the weekend, potentially
forming life-threatening rip currents as they break at the shore.
Stay safe!

&&

.FIRE WEATHER...
Issued at 339 AM AST Fri May 8 2026

Breezy conditions and the lack of significant cloud cover will
also maintain an elevated fire danger risk, particularly across
the southern coastal plains of Puerto Rico, where fuels continue
to dry.

&&

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

$$

SHORT TERM/AVIATION/FIRE...DSR
LONG TERM...ICP
BEACH/MARINE...GRS

NWS SJU Office Area Forecast Discussion