Flash Flood Warning 24, NWS JSJ

573 
WGCA72 TJSJ 302154
FFSSJU

Flash Flood Statement
National Weather Service San Juan PR
554 PM AST Thu Apr 30 2026

PRC047-101-107-302204-
/O.CAN.TJSJ.FF.W.0024.000000T0000Z-260430T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Corozal PR-Morovis PR-Orocovis PR-
554 PM AST Thu Apr 30 2026

...FLASH FLOOD WARNING FOR COROZAL, MOROVIS AND OROCOVIS COUNTIES 
HAS BEEN REPLACED WITH A FLOOD ADVISORY...

&&

LAT...LON 1837 6640 1834 6639 1833 6636 1835 6635
      1836 6636 1836 6634 1837 6631 1833 6628
      1826 6629 1824 6634 1824 6635 1819 6635
      1820 6636 1817 6637 1818 6647 1817 6651
      1825 6651 1825 6645 1837 6646

$$

YZR

Area Forecast Discussion
National Weather Service San Juan PR
123 PM AST Thu Apr 30 2026

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

.KEY MESSAGES...
Updated at 120 PM AST Thu Apr 30 2026

* Showers and thunderstorms are expected to cause urban and small
  stream flooding over the interior and northern Puerto Rico.
  Saturated soils and elevated river levels may worsen impacts on
  vulnerable areas.

* Across the U.S. Virgin Islands, mainly fair weather conditions
  will prevail with a few passing showers moving into the area from
  time to time.

* A gradual transition into drier and stable conditions is expected
  from late Friday onward, with limited shower activity.

* Warmer-than-normal temperatures will continue through the
  weekend, with heat indices reaching or exceeding 100F across
  urban and coastal areas.

&&

.Short Term(This afternoon through Saturday)...
Issued at 120 PM AST Thu Apr 30 2026

Sunny to partly cloudy skies were observed across the U.S. Virgin
Islands during the morning hours, while cloudy to partly sunny
skies prevailed across Puerto Rico. Showers streamed from the Mona
Passage into the Atlantic waters through the early morning hours,
with mostly high clouds and light rain observed over portions of
northwestern Puerto Rico. For the rest of this afternoon, locally
induced showers with isolated thunderstorms are expected to
develop over portions of the interior and north-central PR. Urban
and small stream flooding is possible across these areas. In
addition, light west to southwest steering winds could steer this
activity into portions of west/northwest PR through the evening
hours. Across the USVI, mostly fair weather conditions are
expected to prevail in general, with low-level clouds and mostly
light showers developing downwind of the islands this afternoon.
High temperatures were from the mid-to upper-80s across the lower
elevations of the islands to the upper 70s and low 80s across the
higher elevations. Winds were from the east-southeast up to 12 mph
with higher gusts at times and sea breeze variations across the
western and southern coast of PR.

A drying trend is expected from late Friday and Saturday, as a
surface high pressure strengthens north of the region, and a mid-
to upper-level ridge build from the west, bringing drier air and
more stable conditions in general across the region. The precipitable
water content is expected to drop from 1.90 inches today to near
1.60 inches on Saturday. Having said that, locally induced
afternoon showers are still expected to develop over the western
interior of PR each afternoon, where the flood threat will remain
elevated on Friday.

&&

.Long Term(Sunday through next Thursday)...
Issued at 120 PM AST Thu Apr 30 2026

The long-term period will be dominated by generally tranquil, near-
seasonal conditions for both Puerto Rico and the U.S. Virgin
Islands. Surface high pressure over the central Atlantic will
promote east to southeast winds at 8 to 15 mph through the period.
Aloft, a ridging pattern will persist, supporting stable conditions.
On Sunday, patches of moisture will maintain precipitable water
(PWAT) values near seasonal levels, around 1.5 inches. This will
support brief, passing showers across windward areas during the
morning, followed by scattered afternoon showers and isolated
thunderstorms across the northwestern quadrant of Puerto Rico. Flood
risk will remain low and localized.

A drying trend will develop early next week, leading to improving
conditions. Model guidance indicates PWAT values falling into the
25th percentile. In perspective, PWAT values are expected to be
around 1.25 inches or less. Combined with a mid to upper-level
ridge, this will enhance stability. The driest period is expected
from Monday through Wednesday. Afternoon showers may still develop
due to local effects and diurnal heating, but coverage will be
limited and activity brief. Rain chances will range from 10 to 30
percent each afternoon across northwestern Puerto Rico. By Thursday,
moisture will increase back to near-normal levels as patches of
moisture arrive. At the same time, an upper-level trough will begin
to amplify into the region, increasing instability and the potential
for shower development.

Despite reduced rainfall, the main hazard will be the warm
conditions that will likely persist across the islands. Temperature
guidance at 925 mb, along with a prevailing east to southeasterly
wind flow, suggests values will remain above normal throughout the
forecast period. Daytime highs will range from the upper 80s to low
90s in coastal and urban areas, and from the upper 70s to mid-80s in
higher elevations. Heat indices will reach the upper 90s to low 100s
degrees F daily. A limited heat threat will persist for urban,
coastal, and low-elevation areas. Residents and visitors should stay
hydrated and limit prolonged sun exposure during peak heating
hours.

&&

.AVIATION...
(12Z TAFS)
Issued at 120 PM AST Thu Apr 30 2026

SHRA/TSRA expected to develop over the interior and western PR
thru 30/22z. This should cause mostly VCTS at TJSJ/TJPS/TJBQ.
However, brief periods of MVFR to brief IFR conds cannot be ruled
out at TJBQ with this activity. The 30/12z TJSJ sounding indicated
ESE winds up to 12 kt blo 3000 ft.

&&

.MARINE...
Issued at 120 PM AST Thu Apr 30 2026

A series of highs and frontal boundaries extending from the western
into the Atlantic will prevail over the next few days. As a surface
high pressure moving north of the region will increase the pressure
gradient, strengthening winds and becoming moderate from the east.
Showers and isolated thunderstorms will continue today across local
Atlantic waters, leading to localized hazardous conditions for small
craft. Pulses of a weak, long-period northerly swell will continue
to spread across the Atlantic waters and local passages this
evening, another arriving on Saturday, though seas should remain
between 3 and 5 feet.

&&

.BEACH FORECAST...
Issued at 120 PM AST Thu Apr 30 2026

No changes were introduced to the beach forecast. The small, long-
period northeasterly swell continues to spread across local waters
and passages. Current nearshore buoy observations report seas
between 1 and 2 feet, with periods of 9 to 10 seconds, producing
breaking waves around 3 to 5 feet. Hence, the moderate risk of rip
currents will continue for the northern-exposed beaches of Puerto
Rico, including Culebra, and for St. Thomas and St. John in the U.S.
Virgin Islands. Another swell is expected to arrive by Saturday, but
the risk should remain moderate for the next several days, though
beachgoers must exercise caution as life-threatening rip currents
are still possible along the surf zone.

For additional information and location-specific rip current
details, please visit weather.gov/beach/sju.

&&

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

SHORT TERM/AVIATION...DSR
LONG TERM....YZR
BEACH/MARINE/KEY MESSAGES...MNG

Preliminary Local Storm Report
National Weather Service San Juan PR
445 PM AST Thu Apr 30 2026

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

0340 PM     Flash Flood      2 WNW Hormigueros       18.15N 67.14W
04/30/2026                   Hormigueros        PR   Emergency Mngr

            Emergency managers reported flooding along
            Calle Mirtos in Valle Hermoso Arriba,
            Hormigueros. They stated that a sewer
            overflowed, causing problems at one house
            where water entered the first floor. Based
            on radar estimates, around 2 inches of rain
            fell.

&&

YZR