Flash Flood Warning 12, NWS JSJ

105 
WGCA52 TJSJ 070944
FFWSJU
PRC069-103-071200-
/O.EXT.TJSJ.FF.W.0012.000000T0000Z-260407T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service San Juan PR
544 AM AST Tue Apr 7 2026

The National Weather Service in San Juan has extended the

* Flash Flood Warning for...
  Northeastern Humacao County in Puerto Rico...
  Southwestern Naguabo County in Puerto Rico...

* Until 800 AM AST.

* At 544 AM AST, USGS gauge reports indicated heavy rain falling 
  across the warned area. Between 1 and 2 inches of rain have fallen 
  along Rio Blanco. Additional rainfall amounts of 1 to 2 inches are 
  possible in the warned area. Flash flooding is already occurring 
  along the Rio Blanco.

  HAZARD...Flash flooding caused by heavy rain.

  SOURCE...USGS Rio Blanco Gauges reported.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Road PR-191 and PR-31 intersection with Road #3 (Highway 53)

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 1825 6579 1824 6578 1822 6577 1820 6574
      1818 6572 1818 6573 1818 6574 1819 6575
      1820 6578 1821 6579

FLASH FLOOD...GAUGE INDICATED

$$

CAM

829 
WGCA72 TJSJ 071105
FFSSJU

Flash Flood Statement
National Weather Service San Juan PR
705 AM AST Tue Apr 7 2026

PRC069-103-071115-
/O.CAN.TJSJ.FF.W.0012.000000T0000Z-260407T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Humacao PR-Naguabo PR-
705 AM AST Tue Apr 7 2026

...FLASH FLOOD WARNING FOR SOUTHWESTERN NAGUABO COUNTY HAS BEEN 
REPLACED WITH A FLOOD WARNING...
...FLASH FLOOD WARNING IS CANCELLED FOR NORTHEASTERN HUMACAO 
COUNTY...

&&

LAT...LON 1819 6573 1818 6572 1818 6573 1818 6574
      1819 6575 1819 6576 1820 6576 1820 6577
      1820 6578 1821 6579 1825 6579 1824 6578
      1822 6577 1820 6574

$$

LIS

Area Forecast Discussion
National Weather Service San Juan PR
425 AM AST Tue Apr 7 2026

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

.KEY MESSAGES...
Updated at 416 AM AST Tue Apr 7 2026

* Flooding risk increases this week, highest through midweek.
  Periods of showers and thunderstorms each afternoon and evening
  will increase the risk of urban and small-stream flooding, with
  isolated flash flooding possible across Puerto Rico.

* Dangerous rip currents expected through at least Wednesday,
  increasing late week. Breezy conditions and choppy seas will
  create life- threatening rip currents across most beaches. From
  Thursday onward, northern and eastern beaches of Puerto Rico and
  the U.S. Virgin Islands will see a higher risk due to incoming
  northerly swell.

* Hazardous marine conditions for small craft continue. A Small
  Craft Advisory remains in effect for Atlantic offshore waters
  and the Anegada Passage through at least this afternoon.
  Elsewhere, small craft should exercise caution.

* Breezy to locally windy conditions persist through Saturday.
  Winds will enhance shower activity and contribute to hazardous
  marine and coastal conditions.

* Above-normal heat indices return through Sunday. Elevated heat
  index values will increase the risk of heat-related impacts,
  especially for individuals outdoors without adequate hydration
  or cooling.

&&

.Short Term(Today through Thursday)...
Issued at 416 AM AST Tue Apr 7 2026

Under a southeast wind flow, showers moved inland across the
windward areas of south and east PR, Vieques, Culebra, and the US
Virgin Islands, producing ponding in poorly drained areas.
However, heavy rain impacted the eastern municipalities,
especially the Naguabo region along the Rio Blanco, causing
flooding at the Intersection of PR-191 and PR-31, near the highway
exit, where emergency managers closed the road due to
impassibility. Rain activity moved further inland across portions
of the southern interior near Adjuntas and northeastern PR early
this morning. St Croix also observed descent periods of moderate
to locally heavy rain during this activity, resulting in ponding
in poorly drained areas. Low temperatures ranged from the mid- to
low-70s along the coast to the mid- to upper-60s in the mountains.

Under southeast wind flow and above-normal moisture content,
which will last through the next few days, we expect the
continuation of the wet, unstable weather pattern across PR and
the USVI. Model guidance still suggests a steep lapse rate from
850 to 500 mb, as well as plenty of atmospheric moisture, which,
combined with the excessive heating that 925 mb temperatures are
suggesting, we can expect another round of strong afternoon
convection today and each day during the short-term period. Under
this weather pattern, we have forecast a limited to elevated risk
of flooding for portions of the islands during this period.
Additionally, the 925 mb winds are near or above normal, which
will continue to pool plenty of moisture over the region,
enhancing the showery weather from time to time. Another threat
associated with this pattern is lightning and thunderstorm winds.

Tuesday and Wednesday seem the wettest and most unstable days of
the forecast, becoming less active (at least according to model
guidance) on Thursday. However, we cannot rule out strong
thunderstorms, enhanced by the increasing warming period during
the afternoon across portions of the region. Although we expect
periods with little or no rain, rounds of moderate to locally
heavy rain will impact portions of the islands each day,
especially across the USVI and PR's windward locations overnight
and in the morning, and across the western and northern portions
of PR in the afternoon.

According to the weather pattern described, the threats for
Tuesday and Thursday include: a warm to locally hot heat index
in the afternoons, a limited to elevated risk of flooding rain in
parts of Puerto Rico and the U.S. Virgin Islands, breezy to
locally windy conditions, a moderate to high risk of life-
threatening rip currents, and dangerous lightning associated with
thunderstorms. Please take appropriate precautions during this
time.

&&

.Long Term(Friday through Tuesday)...
Issued at 416 AM AST Tue Apr 7 2026

Conditions will become relatively stable through the long term
period. Expect isolated to scattered showers, mainly during the
afternoon hours due to daytime heating. Activity will be focused
across western and interior Puerto Rico, with minimal impacts
elsewhere. Overall rainfall coverage and intensity should be lower
than previous days. Winds will remain from the east-southeast,
continuing to bring typical pockets of moisture into the region,
from time to time. Model guidance continues to suggests the gradual
return to a wetter and more unstable pattern. An approaching deep-
layered trough combined with above-normal moisture could lead to
increasing shower and thunderstorm activity across the region,
particularly from Monday onwards.

&&

.AVIATION...
(06Z TAFS)
Issued at 416 AM AST Tue Apr 7 2026

VFR conds are expected at local terminals, but MVFR and brief IFR
may occur due to passing rain SHRA/TSRA. Eastern/southern
terminals like TIST/TISX/TJSJ/TJPS will experience SHRA embedded
in the wind flow, especially in the morning and evening. Afternoon
convection will mainly affect western/northern terminals, such as
TJBQ/JSJ. Winds will be from the SE at 5 to 15 kt thru 7/13Z,
then at 10 to 20 knots, with higher gusts near convection and sea
breeze. Expect mnt obsc, reduced visibility in +SHRA/TSRA.

&&

.MARINE...
Issued at 416 AM AST Tue Apr 7 2026

Hazardous marine conditions will persist through at least late this
afternoon as a strong high-pressure system over the Atlantic
maintains moderate to fresh southeasterly winds. Therefore, expect
confused seas, particularly across Atlantic waters and local
passages through at least this evening. Conditions are expected to
gradually improve tonight, with seas subsiding to around 5 feet in
the Atlantic and up to 4 feet in the Caribbean. While trade wind
showers continue to move across the region, isolated to scattered
thunderstorms are likely each afternoon, especially over coastal
waters near western, northern, and northwestern Puerto Rico. Shower
and thunderstorm coverage may increase later this week due to a
series of troughs approaching the region.

&&

.BEACH FORECAST...
Issued at 416 AM AST Tue Apr 7 2026

Although moderate rip current risk will persist for the northern
exposed beaches, life-threatening rip currents are still possible.
Conditions should deteriorate by the end of the week due to a series
of swells arriving and spreading across local Atlantic waters and
passages. Residents and visitors are encouraged to check the latest
beach conditions before heading to the beach at weather.gov/sju and
https://www.weather.gov/beach/forecast?site=sju&action=.

In addition to the life-threatening rip currents, beachgoers
visiting beaches over western and northwestern Puerto Rico in the
afternoons should remain weather alert due to the development of
isolated thunderstorms. Hazards include gusty winds, reduced
visibility due to heavy rainfall, and lightning. Seek shelter inside
a building whenever you hear lightning.

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...None.
VI...None.
AM...Small Craft Advisory until 6 PM AST this evening for AMZ711-723.

&&

KEY MESSAGE/SHORT TERM/AVIATION...CAM
LONG TERM....MMC
MARINE/BEACH FORECAST...CVB

Preliminary Local Storm Report
National Weather Service San Juan PR
355 AM AST Tue Apr 7 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0345 AM     Flood            1 ENE Rio Blanco        18.22N 65.78W
04/07/2026                   Naguabo            PR   Emergency Mngr

            Naguabo Emergency Manager reports that Rio
            Blanco is out of its banks. The Intersection
            of PR-191 and PR-31, near the highway exit,
            was closed due to impassibility.

&&

CAM