Flash Flooding and Flooding in Puerto Rico, April 25 to 27, 2016

Name: Flash Flooding and Flooding in Puerto Rico, April 25 to 27, 2016
Start: 2016-04-25T12:30
End: 2016-04-27T20:45
Location: Puerto Rico

April 25 to 27, 2016 · NWS SJU · 26 events in 12 counties and zones

A surface trough combined with the available moisture produced widespread showers and thunderstorms over mainland Puerto Rico. With the already saturated soils from previous days, urban flooding and flash flood affected the region.

Where it happened

Every event with a place to put it. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 26

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS SJU wrote it up.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS San Juan, PR wrote its last area forecast discussion before the first event at Apr 25, 10:55 AM AST, 1 hour 35 minutes earlier.

Area forecast discussion, Apr 25, 10:55 AM AST, 1 hour 35 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1055 AM AST MON APR 25 2016

.DISCUSSION...A MOIST AND UNSTABLE AIR MASS WILL CONTINUE
ACROSS THE LOCAL ISLANDS TODAY AS TROFINESS ALOFT...AS WELL
AS AT SURFACE PREVAILS ACROSS THE FORECAST AREA. THIS WILL RESULT
IN CLOUDINESS...SHOWERS AND THUNDERSTORMS MAINLY ACROSS THE
CENTRAL AND THE NORTHEASTERN QUADRANT OF PUERTO RICO. SHORT
TERM GRIDS WERE UPDATED TO MATCH CURRENT CONDITIONS. HEAVY
RAINS COULD LEAD TO URBAN AND SMALL STREAM FLOODING.

&&

.AVIATION...SHRA/TSRA DEVELOPMENT AND MOUNTAIN OBSCURATIONS
EXPECTED ACROSS PUERTO RICO THROUGH 25/22Z. THIS MAY RESULT
IN PERIODS OF MVFR CONDS AT JSJ/JPS LATER THIS AFTERNOON.
ELSEWHERE MAINLY VFR WITH PASSING SHOWERS. WINDS WILL BE
LIGHT AND VARIABLE.

&&

.MARINE...TRANQUIL MARINE CONDITIONS EXPECTED DURING THE NEXT
FEW DAYS...HOWEVER FRONTAL BOUNDARY AND ASSOCIATED INDUCED
SURFACE TROUGH MAY PRODUCE LOCALLY HIGHER SEAS AND WINDS IN
THUNDERSTORMS.

&&

.PREV DISCUSSION... /ISSUED /

SYNOPSIS...BROAD MID TO UPPER TROUGH JUST NORTH OF THE REGION
WILL CONTINUE TO SHIFT FARTHER EAST OF THE REGION TODAY THROUGH
TUESDAY. ANOTHER SHORT WAVE TROUGH WILL APPROACH THE REGION LATE
TUESDAY THROUGH WEDNESDAY...THEN SWEEP ACROSS THE REGION DURING
THE LATTER PART OF THE WEEK. WEAK LOW LEVEL CONVERGENCE ZONE AND
MOISTURE REMNANTS FROM AN OLD FRONTAL BOUNDARY WILL CONTINUE TO
SHIFT NORTH AND EAST OF THE REGION TODAY...AS SURFACE HIGH PRESSURE
RIDGE WILL SPREAD ACROSS THE WESTERN ATLANTIC. A LIGHT EAST TO
SOUTHEAST WIND FLOW WILL PREVAIL ACROSS THE REGION DURING THE NEXT
SEVERAL DAYS AS WEAK SURFACE TROUGH WILL LINGER ACROSS THE FORECAST
AREA.

DISCUSSION...
DURING THE OVERNIGHT HOURS...A LINE OF SHOWERS CONTINUED TO FORM
ALONG THE AFOREMENTIONED CONVERGENCE ZONE AND SLOWLY MOVE ONSHORE
ACROSS PARTS OF NORTHWESTERN PUERTO RICO AS WELL AS ACROSS THE
LOCAL ATLANTIC WATERS. THE SHOWER ACTIVITY PRODUCED PERIODS OF
LIGHT TO MODERATE RAINFALL ACROSS THESE AREAS. RAINFALL SO FAR
WAS OF SHORT DURATION WITH NO SIGNIFICANT ACCUMULATIONS. THIS ADDED
MOISTURE ALONG WITH ALREADY AVAILABLE MOISTURE ACROSS THE REGION
WILL INCREASE THE CHANCE OF LOCALLY AND DIURNALLY INDUCED AFTERNOON
CONVECTION ACROSS PARTS OF THE ISLANDS. ISOLATED THUNDERSTORM WILL
REMAIN POSSIBLE MAINLY ACROSS PARTS OF THE NORTHERN HALF OF PUERTO
RICO DURING THE AFTERNOON...AS WELL AS OVER THE OFFSHORE ATLANTIC
WATERS. EXPECT ONLY ISOLATED SHOWERS ACROSS THE REST OF THE ISLANDS
TODAY.

FOR THE REST OF THE WEEK...AS THE AFOREMENTIONED SHORTWAVE TROUGH
APPROACHES THE REGION LATE TUESDAY THROUGH WEDNESDAY...MOISTURE
IS STILL EXPECTED TO POOL ACROSS THE REGION. THIS ALONG WITH THE
FAVORABLE UPPER LEVEL DYNAMICS WILL AGAIN INCREASE THE CHANCES FOR
ENHANCED CONVECTIVE ACTIVITY OVER THE ISLANDS DURING THE LATTER
PART OF THE WORK WEEK. THIS FAIRLY MOIST AND UNSTABLE AIR MASS IS
THEN EXPECTED TO CONTINUE THROUGH FRIDAY.

PREVIOUS NAAPS AEROSOL ANALYSIS PRODUCT AS WELL AS SATELLITE IMAGERY
CONTINUED TO SUGGEST SUSPENDED SAHARAN DUST PARTICULATES ACROSS THE
REGION TODAY. THIS WILL CONTINUE TO AFFECT THE REGION DUE TO COMBINATION
OF THE LIGHT SOUTHERLY LOW LEVEL WIND FLOW...AND MODERATE MID LEVEL
WESTERLIES. THE EXPECTED SHOWER ACTIVITY ACROSS THE REGION WILL HOWEVER
LESSEN THE EFFECTS OF THE DUST CONCENTRATION.

AVIATION...MOSTLY VFR CONDITIONS EXPECTED THIS MORNING ACROSS THE
LOCAL FLYING AREA. -SHRA POSSIBLE AT TJMZ AND TJPS AS SHRA
APPROACHES FROM THE WEST. WINDS WILL BE LIGHT AND VARIABLE EARLY
THIS MORNING INCREASING SLIGHTLY AFTER 25/14Z BUT WILL CONTINUE
LIGHT AND VARIABLE AT TIMES. CLOUDS EXPECTED TO INCREASE TODAY...
GRADUALLY CAUSING CIGS AT AROUND FL080. SHRA/TSRA DEVELOPING ACROSS
CENTRAL PR AFTER 25/16Z...COULD CAUSE VCTS AT TJSJ.

MARINE...SEAS ARE TO SLOWLY IMPROVE THROUGHOUT THE DAY DUE TO THE
SUBSIDING NORTHERLY SWELL AND OVERALL LIGHT TO MODERATE WINDS. THE
HIGH RISK OF RIP CURRENTS IS EXPECTED TO BE REDUCED TO MODERATE BY
6 AM AST THIS MORNING.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  85  77  88  76 /  30  20  20  20
STT  87  78  85  78 /  20  20  20  20

&&

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

23/27

Hazardous weather outlook, Apr 25, 11:26 AM AST, 1 hour 4 minutes before

PERSPECTIVAS SOBRE CONDICIONES PELIGROSAS DEL TIEMPO
SERVICIO NACIONAL DE METEOROLOGIA SAN JUAN PR
1119 AM AST LUNES 25 DE ABRIL DE 2016

AMZ710>745-PRZ001>013-261530-

SAN JUAN Y VECINDAD-NORESTE-SURESTE-INTERIOR ESTE-NORTE CENTRAL-
INTERIOR CENTRAL-PONCE Y VECINDAD-NOROESTE-INTERIOR OESTE-MAYAGUEZ Y
VECINDAD-SUROESTE-CULEBRA-VIEQUES-AGUAS COSTERAS Y LEJOS DE LA COSTA
DEL ATLANTICO Y DEL CARIBE-
1119 AM AST LUNES 25 DE ABRIL DE 2016

ESTA PERSPECTIVA SOBRE LAS CONDICIONES PELIGROSAS DEL TIEMPO ES PARA
PUERTO RICO Y LAS AGUAS COSTERAS ADYACENTES DEL ATLANTICO.

.DIA UNO...ESTA TARDE Y ESTA NOCHE

TRONADAS...EXISTE UNA POSIBILIDAD DE TRONADAS CON LLUVIAS FUERTES Y
BREVES VIENTOS EN RAFAGAS ESTA TARDE A TRAVES DE PORCIONES DEL
INTERIOR CENTRAL Y EL OESTE DE PUERTO RICO.

.INUNDACIONES...FUERTES LLUVIAS PODRIAN DAR PASO A INUNDACIONES EN
 AREAS URBANAS Y EN PEQUENOS RIACHUELOS.

.OLAS...OLEAJE PICADO DE HASTA 5 PIES SE ESPERA A TRAVES DE LAS
AGUAS DEL ATLANTICO Y LOS PASAJES.

.CORRIENTES SUBMARINAS...EXISTE UN RIESGO MODERADO DE CORRIENTES
SUBMARINAS PARA LA COSTA DEL NORTE DE PUERTO RICO.

.DIAS DOS HASTA SIETE...MARTES A DOMINGO

UN RIESGO MODERADO DE CORRIENTES SUBMARINAS CONTINUARA A TRAVES
DE LAS PLAYAS DEL NORTE DE PUERTO RICO DURANTE LOS PROXIMOS DIAS.

.COMUNICADO SOBRE INFORMACION REPORTADA POR OBSERVADORES...

NO SE ANTICIPA ACTIVACION AMPLIA DE OBSERVADORES...SIN EMBARGO...SE
LES EXHORTA A LOS OBSERVADORES INDIVIDUALES A REPORTAR CORRIENTES
SUBMARINAS AL SERVICIO NACIONAL DE METEOROLOGIA EN SAN JUAN.

AMZ715-725-VIZ001-002-261530-

SAN TOMAS SAN JOHN E ISLAS ADYACENTES-SANTA CRUZ-
AGUAS CERCA DE LA COSTA DEL ATLANTICO Y AGUAS COSTERAS
ADYACENTES DEL CARIBE-
1119 AM AST LUNES 25 DE ABRIL DE 2016

ESTA PERSPECTIVA SOBRE LAS CONDICIONES PELIGROSAS DEL TIEMPO ES PARA
LAS ISLAS VIRGENES AMERICANAS Y LAS AGUAS ADYACENTES COSTERAS.

.DIA UNO...ESTA TARDE Y ESTA NOCHE

.OLAS...OLEAJE PICADO DE HASTA 6 PIES SE ESPERA A TRAVES DE LAS
AGUAS DEL ATLANTICO Y LOS PASAJES.

.CORRIENTES SUBMARINAS...EXISTE UN RIESGO MODERADO DE CORRIENTES
SUBMARINAS A TRAVES DE LA COSTA DEL NORTE DE SAN TOMAS.

.DIAS DOS HASTA SIETE...MARTES A DOMINGO

UN RIESGO MODERADO DE CORRIENTES SUBMARINAS CONTINUARA A LO LARGO DE
LAS PLAYAS DEL NORTE DE ALGUNAS DE LAS ISLAS DURANTE LOS PROXIMOS
DIAS.

.COMUNICADO SOBRE INFORMACION REPORTADA POR OBSERVADORES...

NO SE ANTICIPA ACTIVACION AMPLIA DE OBSERVADORES.

The radar

The San Juan radar (TJUA), 32 km away, was scanning. The volume nearest the first event began at 16:30 UTC.

Open the radar archive at this moment

Event by event

11 flash flood, 10 flood, 5 heavy rain. Local standard time, as filed.

Flash Flood, Canovanas

When: April 25, 12:30 PM AST to 3:15 PM AST
Where: Canovanas County, Canovanas to 0.44 mi SSE of Canovanas
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.330, -65.880

A mudslide was reported at Barrio Palma Sola.

Flood, Loiza

When: April 25, 1:25 PM AST to 3:15 PM AST
Where: Loiza County, 3.41 mi SSW of Loiza to 3.39 mi SSW of Loiza
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.373, -65.917

Emergency management reported a partially flooded road in Violeta street at Loiza Aldea.

Flash Flood, Caguas

When: April 25, 2:30 PM AST to 6:00 PM AST
Where: Caguas County, 2.92 mi NNE of Caguas to 2.88 mi NNE of Caguas
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.239, -66.013

House flooded in Santa Margarita street at Santa Elvira urbanization.

Flash Flood, Caguas

When: April 25, 2:30 PM AST to 6:00 PM AST
Where: Caguas County, 2.55 mi N of Caguas to 2.48 mi N of Caguas
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.236, -66.025

FLooding in B street at Urb. Caribe Park in Caguas. Water reached a residence.

Flood, San Juan

When: April 25, 2:30 PM AST to 6:00 PM AST
Where: San Juan County, 3.11 mi W of San Juan to 3.13 mi W of San Juan
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.387, -66.097

Urban flooding near 1350 Ave. Paz Granela in Urb. Santiago Iglesias.

Flash Flood, Caguas

When: April 25, 2:30 PM AST to 6:00 PM AST
Where: Caguas County, 2.12 mi N of Caguas to 2.06 mi N of Caguas
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.231, -66.032

House flooding at Domingo Laza street in Machin urbanization.

Flash Flood, Caguas

When: April 25, 2:30 PM AST to 6:00 PM AST
Where: Caguas County, 2.55 mi NNE of Caguas to 2.64 mi NNE of Caguas
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.236, -66.022

House flooding at calle 13 in Delgado urbanization.

Flood, Caguas

When: April 25, 2:30 PM AST to 6:00 PM AST
Where: Caguas County, 2.41 mi NNE of Caguas to 2.42 mi NNE of Caguas
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.231, -66.013

House flooded at calle 2 in Villa Marina, Caguas.

Flood, Caguas

When: April 25, 2:30 PM AST to 6:00 PM AST
Where: Caguas County, 2.96 mi NNE of Caguas to 2.97 mi NNE of Caguas
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.239, -66.012

Emergency manager reported urban flooding near Santa Maria street in Urb. Santa Elvira in Caguas.

Flood, Caguas

When: April 25, 2:30 PM AST to 6:00 PM AST
Where: Caguas County, 2.87 mi NNW of Caguas to 2.85 mi NNW of Caguas
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.240, -66.042

Urban flooded near Expreso 52 near Las Catalinas Mall.

Flood, Gurabo

When: April 25, 2:30 PM AST to 5:15 PM AST
Where: Gurabo County, 2.1 mi WSW of Gurabo to 2.04 mi WSW of Gurabo
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.259, -66.000

Urban flooding near Las Garzas street in Urb. Santa Barbara in Gurabo. Water reached a residence, house number 6.

Flood, San Juan

When: April 25, 2:30 PM AST to 5:15 PM AST
Where: San Juan County, 2.94 mi NNE of San Juan to 2.96 mi NNE of San Juan
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.422, -66.041

Urban flooding near Alcaniz street in Barrio San Jose in San Juan.

Flood, Gurabo

When: April 25, 2:40 PM AST to 5:30 PM AST
Where: Gurabo County, 2.51 mi SW of Gurabo to 3.05 mi WSW of Gurabo
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.248, -66.001

Urban flooding was reported near A-10 street in Urb. Monte Brisas.

Heavy Rain, Canovanas

When: April 25, 3:15 PM AST to 5:30 PM AST
Where: Canovanas County, 0.71 mi NW of Canovanas to 0.65 mi N of Canovanas
Reported by: Emergency Manager
Coordinates: 18.339, -65.886

A mudslide was reported on road PR-957 Km 4.0 at Peniel sector in Palma Sola.

Heavy Rain, Canovanas

When: April 25, 4:30 PM AST to 5:30 PM AST
Where: Canovanas County, 1.17 mi WNW of Canovanas to 1.29 mi NW of Canovanas
Reported by: Emergency Manager
Coordinates: 18.337, -65.896

A mudslide was reported near PR-185 km 7.0 in Las Vegas sector in Campo Rico.

Flood, Guayanilla

When: April 25, 4:46 PM AST to 5:30 PM AST
Where: Guayanilla County, 0.98 mi ESE of Guayanilla to 1.33 mi ESE of Guayanilla
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.024, -66.767

Flooded roads reported in Bahia sector.

Heavy Rain, Penuelas

When: April 25, 4:46 PM AST to 5:30 PM AST
Where: Penuelas County, 1.47 mi NNW of Penuelas to 1.16 mi NNW of Penuelas
Reported by: Emergency Manager
Coordinates: 18.070, -66.728

A mudslide was reported at road PR-386.

Flood, Canovanas

When: April 25, 5:15 PM AST to 6:15 PM AST
Where: Canovanas County, 3.03 mi NNW of Canovanas to 2.99 mi NNW of Canovanas
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.370, -65.899

A house was reported flooded near street 4 in Quintas sector.

Flash Flood, Penuelas

When: April 25, 5:28 PM AST to 8:00 PM AST
Where: Penuelas County, 3.07 mi NNE of Penuelas to 3.56 mi NE of Penuelas
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.088, -66.696

Rucio river was reported out of its banks.

Flash Flood, Sabana Grande

When: April 25, 7:03 PM AST to 8:00 PM AST
Where: Sabana Grande County, 3.91 mi SSE of Sabana Grande to 4.45 mi SE of Sabana Grande
Cause: Heavy Rain
Reported by: Social Media
Coordinates: 18.032, -66.899

Road PR-121 was reported flooded and closed due to Rio Loco out of its banks.

Heavy Rain, Guanica

When: April 25, 9:33 PM AST to 10:00 PM AST
Where: Guanica County, Guanica to 1.6 mi WSW of Guanica
Reported by: Social Media
Coordinates: 17.980, -66.920

A mudslide was reported near PR-116 at Km 18.7.

Heavy Rain, Canovanas

When: April 26, 10:40 AM AST to 3:15 PM AST
Where: Canovanas County, 71.35 mi ENE of Guanica to 72.19 mi ENE of Guanica
Reported by: Emergency Manager
Coordinates: 18.343, -65.903

A mudslide was reported on road 185 k.m. 7.5, sector Campo Rico.

Flash Flood, Aguadilla

When: April 26, 3:00 PM AST to 5:45 PM AST
Where: Aguadilla County, 2.27 mi WNW of Aguadilla to 2.09 mi WNW of Aguadilla
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.480, -67.153

Roas 467 completely flooded where intersects with road 107.

Flash Flood, Aguadilla

When: April 26, 3:00 PM AST to 5:45 PM AST
Where: Aguadilla County, 0.33 mi W of Aguadilla to 0.07 mi WNW of Aguadilla
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.470, -67.125

Road 459 flooded as it approaches Universidad Interamericana.

Flash Flood, Luquillo

When: April 27, 5:00 PM AST to 8:30 PM AST
Where: Luquillo County, 2.41 mi SW of Luquillo to 2.43 mi SW of Luquillo
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.328, -65.748

Emergency managers reported two persons swept away by flood waters of Mameyes river in sector Puente Roto.

Flash Flood, Naguabo

When: April 27, 8:00 PM AST to 8:45 PM AST
Where: Naguabo County, 3.42 mi W of Naguabo to 3.28 mi W of Naguabo
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.218, -65.782

Road 191 with road 31 were closed due to flood waters.

What these are

Flash Flood: Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.
Flood: Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.
Heavy Rain: Rainfall totals unusual for the place and season that did not produce a flood.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Puerto Rico in 2016 Every state in 2016 This day in weather history Warnings in Puerto Rico, April 2016

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 632054, 632055, 632056, 632057, 632058, 632070, 632073, 632081, 632085, 632086, 632087, 632088, 632358, 632359, 632360, 632361, 632362, 632363, 632364, 632367, 632714, 632757, 632773, 632819, 632822, 632823.