Puerto Rico, 2016

Flash Flooding and Flooding in Puerto Rico, October 18, 2016

October 18, 2016 · NWS SJU · 9 events in 8 counties and zones

Low pressure system north of Hispaniola pulled a band of moisture over the local area which produced torrential rainfall mainly across the eastern interior and south sections of Puerto Rico.

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
$3,000
Crop damage
None recorded
Events
9

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.

Low pressure system north of Hispaniola pulled a band of moisture over the local area which produced torrential rainfall mainly across the eastern interior and south sections of Puerto Rico.

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 Oct 18, 8:56 AM AST, 4 minutes earlier.

Area forecast discussion, Oct 18, 8:56 AM AST, 4 minutes before
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Hazardous weather outlook, Oct 18, 6:20 AM AST, 2 hours 40 minutes before
PERSPECTIVAS SOBRE CONDICIONES PELIGROSAS DEL TIEMPO
SERVICIO NACIONAL DE METEOROLOGIA SAN JUAN PR
555 AM AST MARTES 18 DE OCTUBRE DE 2016

AMZ710>745-PRZ001>013-191000-
SAN JUAN Y VECINDAD-NORESTE-SURESTE-ESTE INTERIOR-
NORTE CENTRAL-CENTRAL INTERIOR-PONCE Y VECINDAD-NOROESTE-
OESTE INTERIOR-MAYAGUEZ Y VECINDAD-SUROESTE-CULEBRA-VIEQUES-
AGUAS COSTERAS Y MAR AFUERA DEL ATLANTICO Y DEL CARIBE-
555 AM AST MARTES 18 DE OCTUBRE DE 2016

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

.DIA UNO...HOY Y ESTA NOCHE

.TRONADAS...EXISTE UNA PROBABILIDAD DE TRONADAS CON LLUVIAS
MODERADAS A FUERTES Y VIENTOS BREVES EN RAFAGAS ESTA TARDE A TRAVES
DE PORCIONES DE SECTORES DEL NORTE...OESTE Y CENTRO DE PUERTO RICO.

.INUNDACIONES...LLUVIAS DE MODERADAS A FUERTES PUDIERAN RESULTAR EN
ACUMULACION DE AGUA EN CARRETERAS Y EN INUNDACIONES MENORES EN AREAS
DE POBRE DRENAJE.

.OLAS...OLEAJE PICADO DE HASTA 6-10 PIES SE ESPERA A TRAVES DE LAS
AGUAS DEL ATLANTICO Y LOS PASAJES LOCALES.

.CORRIENTES SUBMARINAS...EXISTE UN RIESGO ALTO DE CORRIENTES
SUBMARINAS PARA LAS PLAYAS DEL ATLANTICO DE PUERTO RICO.

.CALOR...VIENTOS ALISIOS DEL SURESTE RESULTARAN INDICES DE CALOR
SOBRE LO NORMAL A LO LARGO DE LA COSTA NORTE DE PUERTO RICO.

.DIAS DOS HASTA SIETE...MIERCOLES A LUNES

SE ESPERA UN AUMENTO EN EL POTENCIAL DE DESARROLLO DE AGUACEROS Y
TRONADAS SOBRE PARTES DEL AREA DE PRONOSTICO A MEDIDA QUE UNA BAJA
PRESION SE DESARROLLE NORTE DE LA REGION. INUNDACIONES URBANAS Y DE
RIACHUELOS SON POSIBLES CADA DIA.

SE ESPERAN QUE LAS MAREJADAS DE PERIODO LARGO DEL NORTE CONTINUEN
AFECTANDO LAS ISLAS LOCALES MIERCOLES HASTA EL JUEVES, PARA PRODUCIR
ALTURAS PELIGROSAS DE OLAS ROMPIENTES, CORRIENTES SUBMARINAS Y
EROSION COSTERA A LO LARGO DE LAS COSTAS DE LAS AGUAS DEL ATLANTICO
Y LOS PASAJES DEL CARIBE.

.COMUNICADO SOBRE INFORMACION REPORTADA POR OBSERVADORES...

NO SE ANTICIPA ACTIVACION AMPLIA DE OBSERVADORES, SIN EMBARGO SE
INVITA A LOS OBSERVADORES A REPORTAR CORRIENTES SUBMARINAS Y
INUNDACIONES MENORES AL SERVICIO NACIONAL DE METEOROLOGIA EN SAN
JUAN.

AMZ715-725-VIZ001-002-191000-
SAN TOMAS SAN JOHN E ISLAS ADYACENTES-SANTA CRUZ-
AGUAS CERCA DE LA COSTA DEL ATLANTICO Y AGUAS COSTERAS ADYACENTES
DEL CARIBE-
555 AM AST MARTES 18 DE OCTUBRE DE 2016

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

.DIA UNO...HOY Y ESTA NOCHE

.OLAS...OLEAJE PICADO DE 6-10 PIES SE ESPERA A TRAVES DE LAS
AGUAS DEL ATLANTICO Y LOS PASAJES LOCALES.

.CORRIENTES SUBMARINAS...EXISTE UN RIESGO ALTO DE CORRIENTES
SUBMARINAS PARA TODAS LAS PLAYAS DEL NORTE DE LAS ISLAS VIRGENES
AMERICANAS.

.DIAS DOS HASTA SIETE...MIERCOLES A LUNES

SE ESPERAN QUE LAS MAREJADAS DE PERIODO LARGO DEL NORTE CONTINUEN
AFECTANDO LAS ISLAS LOCALES MIERCOLES HASTA EL JUEVES, PARA PRODUCIR
ALTURAS PELIGROSAS DE OLAS ROMPIENTES, CORRIENTES SUBMARINAS Y
EROSION COSTERA A LO LARGO DE LAS COSTAS DE LAS AGUAS DEL ATLANTICO
Y LOS PASAJES DEL CARIBE.

.COMUNICADO SOBRE INFORMACION REPORTADA POR OBSERVADORES...

NO SE ANTICIPA ACTIVACION AMPLIA DE OBSERVADORES, SIN EMBARGO SE
INVITA A LOS OBSERVADORES A REPORTAR CORRIENTES SUBMARINAS Y
INUNDACIONES MENORES AL SERVICIO NACIONAL DE METEOROLOGIA EN SAN
JUAN.

In the hours before

Special weather statement, Oct 18, 7:28 AM AST, 1 hour 32 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SAN JUAN PR
728 AM AST TUE OCT 18 2016

PRZ006-007-009-181230-
PONCE AND VICINITY-CENTRAL INTERIOR-WESTERN INTERIOR-
728 AM AST TUE OCT 18 2016

...A STRONG THUNDERSTORM WILL AFFECT ADJUNTAS...PENUELAS...JUANA
DIAZ...PONCE...SOUTHEASTERN YAUCO...OROCOVIS...GUAYANILLA...UTUADO...
VILLALBA...COAMO...CIALES AND JAYUYA MUNICIPALITIES...

AT 726 AM AST...STRONG THUNDERSTORMS MOVED INLAND ACROSS THE
SOUTHWEST AND SOUTH CENTRAL PUERTO RICO OVER THE NEXT HOUR OR SO.
TORRENTIAL RAINFALL, GUSTY WINDS UP TO 30 MPH AND FREQUENT LIGHTNING
IS POSSIBLE WITH THIS THUNDERSTORM.

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM AND MAY CAUSE
LOCALIZED FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM.
LIGHTNING CAN STRIKE 10 MILES AWAY FROM A THUNDERSTORM. SEEK A SAFE
SHELTER INSIDE A BUILDING OR VEHICLE.

LAT...LON 1819 6638 1799 6675 1800 6676 1799 6676
      1801 6677 1800 6680 1799 6680 1799 6679
      1797 6679 1806 6690 1832 6664
TIME...MOT...LOC 1126Z 226DEG 28KT 1808 6675

ER
Special weather statement, Oct 18, 7:57 AM AST, 1 hour 3 minutes before
COMUNICADO ESPECIAL SOBRE LAS CONDICIONES DEL TIEMPO
SERVICIO NACIONAL DE METEOROLOGIA SAN JUAN PR
607 AM AST MARTES 18 DE OCTUBRE DE 2016

PRZ007>011-181130-
SUROESTE-PONCE Y VECINDAD-NOROESTE-MAYAGUEZ Y VECINDAD-
OESTE INTERIOR-
607 AM AST MARTES 18 DE OCTUBRE DE 2016

...UNA AREA DE FUERTES TRONADAS AFECTARAN A CAMUY...ISABELA...
QUEBRADILLAS...SABANA GRANDE...SAN SEBASTIAN...WESTERN YAUCO...SAN
GERMAN...GUAYANILLA...MARICAO...LARES...HORMIGUEROS...MAYAGUEZ...
MOCA...GUANICA...LAJAS...ANASCO...RINCON...AGUADA...AGUADILLA...LAS
MARIAS Y CABO ROJO...

A LAS 6:04 AM AST...UNA AREA INTENSA DE AGUACEROS Y FUERTES TRONADAS
AFECTAN EL OESTE DE PUERTO RICO. SE ESPERAN RAYOS
PELIGROSOS...LLUVIAS TORRENCIALES Y RAFAGAS DE VIENTOS. A MEDIDA
QUE PASEN ESTAS TORMENTAS...SE ESPERA FUERTES VIENTOS ALREDEDOR
DE 30-35 NUDOS. ESTA ACTIVIDAD CONTINUARA DURANTE LA PROXIMA HORA
O MAS A TRAVES DE ESTOS MUNICIPIOS.

VIENTOS EN EXCESO DE 30 MPH SON POSIBLES CON ESTA TRONADA.

LLUVIAS TORRENCIALES ESTAN OCURRIENDO CON ESTA TORMENTA Y PODRIAN
CAUSAR INUNDACIONES LOCALIZADAS. NO INTENTE CONDUCIR SU VEHICULO A
TRAVES DE CARRETERAS INUNDADAS.

RAYOS FRECUENTES DE NUBE A SUELO ESTAN OCURRIENDO CON ESTA TRONADA.
LOS RAYOS PUEDEN CAER A 10 MILLAS DE DISTANCIA DE UNA TRONADA.
BUSQUE REFUGIO SEGURO DENTRO DE UN EDIFICIO O VEHICULO.

FC/RVT
Special weather statement, Oct 18, 8:00 AM AST, 1 hour before
COMUNICADO ESPECIAL SOBRE LAS CONDICIONES DEL TIEMPO
SERVICIO NACIONAL DE METEOROLOGIA SAN JUAN PR
728 AM AST MARTES 18 DE OCTUBRE DE 2016

PRZ006-007-009-181230-
PONCE Y VECINDAD-INTERIOR CENTRAL-OESTE INTERIOR-
728 AM AST MARTES 18 DE OCTUBRE DE 2016

...UNA AREA DE FUERTES TRONADAS AFECTARAN A ADJUNTAS...PENUELAS...JUANA
DIAZ...PONCE...SOUTHEASTERN YAUCO...OROCOVIS...GUAYANILLA...UTUADO...
VILLALBA...COAMO...CIALES Y JAYUYA...

A LAS 7:26 AM AST...TRONADAS FUERTES SE MUEVEN SOBRE EL SUROESTE
Y SUR CENTRAL DE PUERTO RICO DURANTE LAS PROXIMAS HORAS. LLUVIAS
TORRENCIALES...RAFAGAS DE VIENTOS HASTA 30 NUDOS Y
RAYOS FRECUENTES SON POSIBLES CON ESTAS TORMENTAS.

LLUVIAS TORRENCIALES ESTAN OCURRIENDO CON ESTA TORMENTA Y PODRIAN
CAUSAR INUNDACIONES LOCALIZADAS. NO INTENTE CONDUCIR SU VEHICULO A
TRAVES DE CARRETERAS INUNDADAS.

RAYOS FRECUENTES DE NUBE A SUELO ESTAN OCURRIENDO CON ESTA TRONADA.
LOS RAYOS PUEDEN CAER A 10 MILLAS DE DISTANCIA DE UNA TRONADA.
BUSQUE REFUGIO SEGURO DENTRO DE UN EDIFICIO O VEHICULO.

ER/RVT
Special weather statement, Oct 18, 8:01 AM AST, 59 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SAN JUAN PR
801 AM AST TUE OCT 18 2016

PRZ001-004>007-009-181245-
NORTH CENTRAL-PONCE AND VICINITY-SAN JUAN AND VICINITY-CENTRAL
INTERIOR-EASTERN INTERIOR-WESTERN INTERIOR-
801 AM AST TUE OCT 18 2016

...A LINE OF STRONG THUNDERSTORMS IS AFFECTING THE CENTRAL
INTERIOR...

AT 757 AM AST...A LINE OF STRONG THUNDERSTORMS IS MOVING QUICKLY
ACROSS THE CENTRAL PUERTO RICO. TORRENTIAL RAINFALL...GUSTY WINDS OF
30-40 MPH AND FREQUENT LIGHTNING WILL ACCOMPANY THIS LINE OF
THUNDERSTORMS.

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM AND MAY CAUSE
LOCALIZED FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM.
LIGHTNING CAN STRIKE 10 MILES AWAY FROM A THUNDERSTORM. SEEK A SAFE
SHELTER INSIDE A BUILDING OR VEHICLE.

LAT...LON 1833 6636 1836 6635 1837 6630 1833 6628
      1832 6621 1828 6621 1826 6619 1828 6615
      1813 6625 1797 6654 1796 6658 1796 6662
      1798 6663 1805 6663 1817 6670 1819 6678
      1834 6659 1838 6642
TIME...MOT...LOC 1157Z 237DEG 39KT 1823 6662 1821 6655 1817 6651 1809
6650 1803 6654

ER
Special weather statement, Oct 18, 8:01 AM AST, 59 minutes before
SPECIAL WEATHER STATEMENT...CORRECTED
NATIONAL WEATHER SERVICE SAN JUAN PR
801 AM AST TUE OCT 18 2016

PRZ006-007-009-181315-
PONCE AND VICINITY-CENTRAL INTERIOR-WESTERN INTERIOR-
801 AM AST TUE OCT 18 2016

...A STRONG THUNDERSTORM WILL AFFECT ADJUNTAS...PENUELAS...JUANA
DIAZ...PONCE...SOUTHEASTERN YAUCO...OROCOVIS...GUAYANILLA...UTUADO...
VILLALBA...COAMO...CIALES AND JAYUYA MUNICIPALITIES...

AT 726 AM AST...STRONG THUNDERSTORMS MOVING INLAND ACROSS THE
SOUTHWEST AND SOUTH CENTRAL PUERTO RICO OVER THE NEXT HOUR OR SO.
TORRENTIAL RAINFALL, GUSTY WINDS UP TO 30 MPH AND FREQUENT
LIGHTNING IS POSSIBLE WITH THIS THUNDERSTORM.

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM AND MAY CAUSE
LOCALIZED FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM.
LIGHTNING CAN STRIKE 10 MILES AWAY FROM A THUNDERSTORM. SEEK A SAFE
SHELTER INSIDE A BUILDING OR VEHICLE.

LAT...LON 1819 6638 1799 6675 1800 6676 1799 6676
      1801 6677 1800 6680 1799 6680 1799 6679
      1797 6679 1806 6690 1832 6664
TIME...MOT...LOC 1126Z 226DEG 28KT 1808 6675

ER
Special weather statement, Oct 18, 8:07 AM AST, 53 minutes before
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The radar

The San Juan radar (TJUA), 11 km away, was scanning. The volume nearest the first event began at 12:59 UTC.

Open the radar archive at this moment

Event by event

3 heavy rain, 3 flash flood, 2 flood, 1 thunderstorm wind. Local standard time, as filed.

Heavy Rain, Caguas

When
October 18, 9:00 AM AST to 6:00 PM AST
Where
Caguas County, Caguas to 3.38 mi SE of Caguas
Reported by
Emergency Manager
Coordinates
18.200, -66.030

Heavy Rainfall across Barrio San Salvador led to a mudslide on road PR-765 Km 7.9.

Flood, Ponce

When
October 18, 9:00 AM AST to 6:00 PM AST
Where
Ponce County, 1.88 mi SSE of Ponce to 1.73 mi SSE of Ponce
Cause
Heavy Rain
Reported by
Emergency Manager
Coordinates
18.026, -66.606

Urban flooding reported on road 1A Barrio Arenas and adjacent to the public housing Los Rosales.

Heavy Rain, Sabana Grande

When
October 18, 9:00 AM AST to 6:00 PM AST
Where
Sabana Grande County, 5.12 mi NNE of Sabana Grande to 5.33 mi NNE of Sabana Grande
Reported by
Emergency Manager
Coordinates
18.152, -66.913

Heavy rainfall led to a mudslide on road PR-365 Km 2.6.

Flood, Guayanilla

When
October 18, 9:00 AM AST to 6:00 PM AST
Where
Guayanilla County, 1.2 mi NW of Guayanilla to 1.55 mi NW of Guayanilla
Cause
Heavy Rain
Reported by
Emergency Manager
Coordinates
18.041, -66.794

Urban flooding was reported on Barrio Piedras Blancas and Barrio Macana on road PR-132.

Flash Flood, Cabo Rojo

When
October 18, 1:29 PM AST to 5:00 PM AST
Where
Cabo Rojo County, Cabo Rojo to 1.41 mi ENE of Cabo Rojo
Cause
Heavy Rain
Property damage
$2,000
Reported by
911 Call Center
Coordinates
18.030, -67.130

Flooded residence in Reparto Saman,at the end of street 4.

Flash Flood, Mayaguez

When
October 18, 1:30 PM AST to 5:00 PM AST
Where
Mayaguez County, 3.47 mi WSW of Mayaguez to 2.78 mi WSW of Mayaguez
Cause
Heavy Rain
Reported by
Emergency Manager
Coordinates
18.182, -67.169

Road PR-102 was reported flooded and closed as water level rose to one feet above ground level.

Flash Flood, Salinas

When
October 18, 2:35 PM AST to 5:00 PM AST
Where
Salinas County, 2.92 mi SE of Salinas to 3.04 mi SE of Salinas
Cause
Heavy Rain
Reported by
Emergency Manager
Coordinates
17.971, -66.218

Two houses at sector San Felipe were reported flooded in PR-3.

Thunderstorm Wind, Utuado

When
October 18, 8:30 PM AST
Where
Utuado County, 3.2 mi SE of Utuado to 8.05 mi ENE of Utuado
Measured
35 kt (40 mph) estimated gust
Property damage
$1,000
Reported by
Emergency Manager
Coordinates
18.244, -66.660

Many trees down either blocking the roads or hanging on the electrical power lines along road PR-140 and PR-141.

Heavy Rain, Utuado

When
October 18, 9:00 PM AST
Where
Utuado County, 8.14 mi ENE of Utuado to 7.03 mi ENE of Utuado
Reported by
911 Call Center
Coordinates
18.304, -66.581

Mudslide at road PR-140 that blocked the doors to a local church at Barrio Mameyes.

What these are

Heavy Rain
Rainfall totals unusual for the place and season that did not produce a flood.
Flood
Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.
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.
Thunderstorm Wind
Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.

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

The same day elsewhere

More

Every storm in Puerto Rico in 2016Every state in 2016This day in weather historyWarnings in Puerto Rico, October 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 2026-10-01. Each event’s entry at NCEI: 663757, 663758, 663759, 663760, 663761, 663762, 664147, 664148, 664149.