Flash Flooding and Flood in Puerto Rico, May 28 to 29, 2010

Name: Flash Flooding and Flood in Puerto Rico, May 28 to 29, 2010
Start: 2010-05-28T06:43
End: 2010-05-29T02:15
Location: Puerto Rico

May 28 to 29, 2010 · NWS SJU · 12 events in 11 counties and zones

Deep moisture, combined with favorable atmospheric conditions, local effects and a low level trough to the north of Puerto Rico, brought widespread flooding rains across Puerto Rico during the last few days of the month. Unfortunately, with this flood event, there were a few fatalities due to people driving across low water crossings and also reported, was a lightning strike in Carolina, PR in…

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: 2
Injuries: 1
Property damage: $30,000
Crop damage: None recorded
Events: 12

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 May 28, 5:30 AM AST, 1 hour 13 minutes earlier.

Area forecast discussion, May 28, 5:30 AM AST, 1 hour 13 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
530 AM AST FRI MAY 28 2010

.SYNOPSIS...GENERALLY UNSETTLED WEATHER IS EXPECTED TO CONTINUE
ACROSS THE LOCAL ISLANDS THROUGH THE END OF THE WEEK..AND PROBABLY
BEYOND...IN A VERY MOIST SOUTHERLY WIND FLOW.

&&

.DISCUSSION...PUERTO RICO HAS BEEN FORTUNATE...AT LEAST FOR NOW.
AN EXTENSIVE AREA OF DEEP CONVECTION HAS PREVAILED ACROSS THE
CARIBBEAN WATERS OVERNIGHT AND EARLY THIS MORNING. THIS AREA HAS
BEEN MOVING EAST NORTHEAST...AND IS EXPECTED TO APPROACH MAINLY
THE ISLAND OF SAINT CROIX IN THE U.S. VIRGIN ISLANDS LATER THIS
MORNING. TOPS OF -84C HAS BEEN OBSERVED IN LATEST IR IMAGES IN THE
DEEPEST CONVECTION ASSOCIATED WITH THIS FEATURE. ALTHOUGH THIS
FEATURE MISSED PUERTO RICO...SOME SHOWERS WERE OBSERVED ACROSS THE
SOUTHWESTERN CORNER OF PUERTO RICO...PRODUCING PERIODS OF HEAVY
RAIN. ALL MODELS CONTINUE TO AGREED THAT A COMPLEX WEATHER PATTERN
WILL AFFECT THE LOCAL AREA THROUGH AT LEAST SUNDAY. THE MAIN TWO
WEATHER FEATURES WHICH WILL BE RESPONSIBLE FOR THIS WET
SCENARIO...IS A BROAD TROUGH WHICH WILL MOVE ACROSS PUERTO RICO
AND THE U.S. VIRGIN ISLANDS BETWEEN THIS MORNING AND
SATURDAY...WITH ANOTHER DEVELOPING SURFACE LOW PRESSURE...APPROACHING
THE LOCAL AREA FROM THE WEST...AND THIS SECOND LOW IS IN
FACT...THE ONE THAT PROBABLY WILL HAVE A BIGGER IMPACT ON OUR
WEATHER...WITH THE BIGGEST IMPACT OF THIS SYSTEM EXPECTED TO START
THIS SATURDAY NIGHT AND LASTING PROBABLY THROUGH SUNDAY NIGHT.
COMPUTER MODELS NOW MAINTAINS ENOUGH MOISTURE AROUND TO KEEP
UNSETTLED WEATHER CONDITIONS THROUGH AT LEAST MONDAY. THE
SOUTHWESTERLY WINDS WILL BRING PLENTY OF MOISTURE FROM THE DEEP
TROPICS ACROSS THE LOCAL AREA. DUE TO THIS EXPECTED WEATHER
SCENARIO...AND DUE TO ALREADY SATURATED SOILS...A FLASH FLOOD
WATCH CONTINUES IN EFFECT TO AT LEAST SATURDAY EVENING FOR ALL
PUERTO RICO AND THE U.S. VIRGIN ISLANDS. LOCAL RESIDENTS AND
EMERGENCY MANAGEMENT OFFICIALS ARE ENCOURAGED TO MONITOR THIS
DEVELOPING WEATHER SITUATION FOR THE END OF THE WEEK...AS THERE IS
STILL QUITE SOME UNCERTAINTY IN THE EXACT TIMING AND RAINFALL
TOTALS EXPECTED WITH THIS DEEP TROPICAL TONGUE OF MOISTURE
EXPECTED TO MOVE ACROSS THE LOCAL ISLANDS.

&&

.AVIATION...OCCASIONAL MVFR CONDS AND TEMPORARY IFR CONDITIONS WILL
BECOME MORE PREVALENT ACROSS ALL OF THE LOCAL ISLANDS AND TAF SITES
DURING THE NEXT 12 TO 24 HOURS...IN DEVELOPING NUMEROUS TO
WIDESPREAD SHOWERS AND ISOLATED TO SCATTERED THUNDERSTORMS.
PREVAILING VFR CONDS ARE EXPECTED ACROSS TKPK AND TNCM...WITH BRIEF
MVFR CONDITIONS POSSIBLE.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  88  77  90  79 /  80  70  70  30
STT  85  78  86  80 /  80  80  70  60

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...FLASH FLOOD WATCH THROUGH SATURDAY EVENING FOR CENTRAL INTERIOR-
     CULEBRA-EASTERN INTERIOR-MAYAGUEZ AND VICINITY-NORTH
     CENTRAL-NORTHEAST-NORTHWEST-PONCE AND VICINITY-SAN JUAN AND
     VICINITY-SOUTHEAST-SOUTHWEST-VIEQUES-WESTERN INTERIOR.

VI...FLASH FLOOD WATCH THROUGH SATURDAY EVENING FOR ST CROIX-ST.
     THOMAS/ST. JOHN/ADJACENT ISLANDS.

&&

06/71

Hazardous weather outlook, May 28, 6:00 AM AST, 43 minutes before

HAZARDOUS WEATHER OUTLOOK FOR PUERTO RICO AND THE U.S. VIRGIN
ISLANDS
NATIONAL WEATHER SERVICE SAN JUAN PR
600 AM AST FRI MAY 28 2010

AMZ710>745-PRZ001>013-291000-
SAN JUAN AND VICINITY-NORTHEAST-SOUTHEAST-EASTERN INTERIOR-
NORTH CENTRAL-CENTRAL INTERIOR-PONCE AND VICINITY-NORTHWEST-
WESTERN INTERIOR-MAYAGUEZ AND VICINITY-SOUTHWEST-CULEBRA-VIEQUES-
THE NEARSHORE AND OFF SHORE ATLANTIC AND CARIBBEAN COASTAL WATERS-
600 AM AST FRI MAY 28 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PUERTO RICO AND THE
ADJACENT COASTAL WATERS.

.DAY ONE...TODAY AND TONIGHT

A VERY MOIST AND UNSTABLE AIR MASS WILL COMBINE WITH LOCAL
EFFECTS AND FAVORABLE MID TO UPPER LEVEL CONDITIONS TODAY THROUGH
TONIGHT...TO PRODUCE NUMEROUS TO WIDESPREAD SHOWERS AND ISOLATED
TO SCATTERED THUNDERSTORMS ACROSS THE LOCAL ISLANDS. PERIODS OF
HEAVY RAINFALL AND URBAN AND SMALL STREAM FLOODING ARE STILL
EXPECTED IN MANY AREAS...WITH THE POTENTIAL FOR MORE SIGNIFICANT
FLASH AND RIVER FLOODING. A FLASH FLOOD WATCH REMAINS IN EFFECT
FOR ALL OF PUERTO RICO AND CULEBRA AND VIEQUES TODAY THROUGH
TONIGHT.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

A VERY MOIST AND UNSTABLE AIR MASS WILL CONTINUE TO COMBINE WITH
LOCAL EFFECTS AND FAVORABLE MID TO UPPER LEVEL CONDITIONS FOR
SATURDAY AND PROBABLY SUNDAY ALSO...TO PRODUCE ADDITIONAL SHOWERS
AND THUNDERSTORMS ACROSS THE LOCAL ISLANDS. PERIODS OF HEAVY
RAINFALL AND URBAN AND SMALL STREAM FLOODING ARE EXPECTED IN MANY
AREAS...WITH THE POTENTIAL FOR MORE SIGNIFICANT FLASH AND RIVER
FLOODING. A FLASH FLOOD WATCH WILL REMAIN IN EFFECT FOR ALL OF
PUERTO RICO AND CULEBRA AND VIEQUES THROUGH SATURDAY EVENING.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS REQUESTED TODAY THROUGH AT LEAST SATURDAY
EVENING. ANY REPORTS OF HEAVY RAINFALL OR FLOODING WOULD BE
GREATLY APPRECIATED.

AMZ715-725-VIZ001-002-291000-
ST. THOMAS ST. JOHN ADJACENT ISLANDS-ST CROIX-
NEARSHORE ATLANTIC AND ADJACENT CARIBBEAN COASTAL WATERS-
600 AM AST FRI MAY 28 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE U.S. VIRGIN ISLANDS AND
THE ADJACENT COASTAL WATERS.

.DAY ONE...TODAY AND TONIGHT

A VERY MOIST AND UNSTABLE AIR MASS WILL COMBINE WITH LOCAL
EFFECTS AND FAVORABLE MID TO UPPER LEVEL CONDITIONS TODAY THROUGH
TONIGHT...TO PRODUCE NUMEROUS TO WIDESPREAD SHOWERS AND ISOLATED
THUNDERSTORMS ACROSS THE LOCAL ISLANDS. PERIODS OF HEAVY RAINFALL
AND URBAN AND GUT FLOODING ARE EXPECTED IN MANY AREAS...WITH THE
POTENTIAL FOR MORE SIGNIFICANT FLASH FLOODING. A FLASH FLOOD WATCH
REMAINS IN EFFECT FOR ALL OF THE U.S. VIRGIN ISLANDS TODAY THROUGH
TONIGHT.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

A VERY MOIST AND UNSTABLE AIR MASS WILL CONTINUE TO COMBINE WITH
LOCAL EFFECTS AND FAVORABLE MID TO UPPER LEVEL CONDITIONS FOR
SATURDAY AND PROBABLY SUNDAY ALSO...TO PRODUCE ADDITIONAL SHOWERS
AND THUNDERSTORMS ACROSS THE LOCAL ISLANDS. PERIODS OF HEAVY
RAINFALL AND URBAN AND GUT FLOODING ARE EXPECTED IN MANY AREAS...
WITH THE POTENTIAL FOR MORE SIGNIFICANT FLASH FLOODING. A FLASH
FLOOD WATCH WILL REMAIN IN EFFECT FOR ALL OF THE U.S. VIRGIN
ISLANDS THROUGH SATURDAY EVENING.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS REQUESTED TODAY THROUGH AT LEAST SATURDAY
EVENING. ANY REPORTS OF HEAVY RAINFALL OR FLOODING WOULD BE
GREATLY APPRECIATED.

The radar

The San Juan radar (TJUA), 39 km away, was scanning. The volume nearest the first event began at 10:44 UTC.

Open the radar archive at this moment

Event by event

7 flash flood, 3 heavy rain, 1 flood, 1 lightning. Local standard time, as filed.

Flood, Naguabo

When: May 28, 6:43 AM AST to 9:45 AM AST
Where: Naguabo County, Naguabo to 1.31 mi ENE of Naguabo
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.220, -65.730

Route 31 was reported flooded in Naguabo.

Flash Flood, Villalba

When: May 28, 7:50 AM AST
Where: Villalba County, 1.88 mi WNW of Villalba to 0.71 mi WNW of Villalba
Cause: Heavy Rain
Property damage: $5,000
Reported by: Emergency Manager
Coordinates: 18.131, -66.496

River Rio Achiote overflowed its banks, flooding road 151. Road 151 flooded due to Achiote river out of its banks. Flooding was also reported along road 162 at Barrio Camarones, Palmarejo sector, and at la Vega Sector. Roads 149 and 151 in Bo. Pino also flooded. A house was reported flooded in Bo Pino.

Flash Flood, Adjuntas

When: May 28, 7:52 AM AST
Where: Adjuntas County, 0.93 mi ENE of Adjuntas to 1.28 mi NE of Adjuntas
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.177, -66.738

Flooding was reported along roads 10 and 123 in the Guanico sector.

Lightning, Carolina

When: May 28, 1:30 PM AST
Where: Carolina County, 3.1 mi NW of Carolina to 3.48 mi NNW of Carolina
Injuries: 1 direct, 0 indirect
Reported by: Newspaper
Coordinates: 18.407, -65.978

An 8 year old girl was injured when she was struck by lightning in the front yard of her home in the Valle Arriba Heights neighborhood. She received treatment for lightning related injuries.

Flash Flood, Utuado

When: May 28, 6:41 PM AST to 8:30 PM AST
Where: Utuado County, 1.72 mi NNW of Utuado to 1.9 mi NNW of Utuado
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.293, -66.709

River Rio Grande de Arecibo overflowed its banks, flooding Highway 10 and road 123.

Heavy Rain, Aibonito

When: May 28, 7:10 PM AST to 10:10 PM AST
Where: Aibonito County, 1.81 mi NW of Aibonito
Reported by: Emergency Manager
Coordinates: 18.140, -66.268

Urban flooding reported in downtown Aibonito.

Flash Flood, Ponce

When: May 28, 7:11 PM AST to 10:00 PM AST
Where: Ponce County, 2.09 mi SE of Ponce to 2.38 mi SE of Ponce
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.026, -66.601

Flooding was reported at route 14 ramp near the La Rambla shopping center and on route 132 near The Jardines del Caribe communnity.

Flash Flood, Barranquitas

When: May 28, 7:30 PM AST to 9:30 PM AST
Where: Barranquitas County, 2.02 mi WSW of Barranquitas
Cause: Heavy Rain
Deaths: 2 direct, 0 indirect
Property damage: $10,000
Reported by: Newspaper
Coordinates: 18.188, -66.348

River Botijas overflowed its banks along road 720, km. 0.3 in Barrio Palo Hincado, in the border between the Barranquitas and Orocovis municipalities. Flash flooding killed|two people who drowned when their truck Ford F150 car was swept away by river Botijas flood waters.

Heavy Rain, Cidra

When: May 28, 7:31 PM AST to 10:31 PM AST
Where: Cidra County, Cidra
Reported by: Emergency Manager
Coordinates: 18.170, -66.150

Flooding was reported on road 729 in barrio Toita.

Flash Flood, San Lorenzo

When: May 28, 7:50 PM AST to May 29, 2:15 AM AST
Where: San Lorenzo County, 0.51 mi W of San Lorenzo to 0.46 mi SW of San Lorenzo
Cause: Heavy Rain
Reported by: Emergency Manager
Coordinates: 18.149, -65.978

River Cayaguas overflowed its banks and flooded road 9912.

Heavy Rain, Barranquitas

When: May 28, 8:30 PM AST to 11:30 PM AST
Where: Barranquitas County, Barranquitas
Reported by: Emergency Manager
Coordinates: 18.200, -66.320

Flooding was reported in Pinona Bo Palo Hincado.

Flash Flood, Manati

When: May 28, 8:30 PM AST to 11:30 PM AST
Where: Manati County, 3.06 mi WNW of Manati to 2.84 mi WNW of Manati
Cause: Heavy Rain
Property damage: $15,000
Reported by: Emergency Manager
Coordinates: 18.429, -66.526

Rio Grande de Manati overflowed its banks and flooded Highway 2 and road 667 in the Paso Real and Cachete sectors. Several homes were flooded in the Paso Real Sector.

The people who died

As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.

Event	Date	Age	Sex	Where	Kind
Flash Flood, Barranquitas	2010-05-28	58	Male	Vehicle/Towed Trailer	Direct
Flash Flood, Barranquitas	2010-05-28	54	Female	Vehicle/Towed Trailer	Direct

What these are

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.
Lightning: A lightning strike that killed, injured or caused damage.
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 2010 Every state in 2010 This day in weather history Warnings in Puerto Rico, May 2010

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: 235327, 235328, 235329, 237243, 235330, 235331, 235332, 237216, 235333, 235359, 235360, 235361.