Puerto Rico, 2017

Flash Flooding in Puerto Rico, September 6 to 7, 2017

September 6 to 7, 2017 · NWS SJU · 25 events in 25 counties and zones

Hurricane Irma was a category 5 storm with max winds of 185 mph, mainly confined in the northeast quadrant. The direction of the storm was towards the west northwest.

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
$759 million
Crop damage
None recorded
Events
25

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.

Hurricane Irma was a category 5 storm with max winds of 185 mph, mainly confined in the northeast quadrant. The direction of the storm was towards the west northwest. Saint Thomas and Saint John experienced the southern eyewall with winds in excess of 115 mph with Culebra also experiencing Hurricane force gusts in excess of 100 mph. Mainland Puerto Rico, Vieques, and Saint Croix experienced mainly tropical storm force winds. The eye of Irma as it was tracking towards the west-northwest passed 30 miles north of San Juan.

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 Sep 6, 12:09 PM AST, 2 hours 35 minutes earlier.

Area forecast discussion, Sep 6, 12:09 PM AST, 2 hours 35 minutes before
Area Forecast Discussion
National Weather Service San Juan PR
1209 PM AST Wed Sep 6 2017

...Hurricane conditions expected across Puerto Rico and the U.S.
Virgin Islands this afternoon and tonight...

.UPDATE...Category 5 Hurricane Irma is now bearing down on Saint
John and Saint Thomas. The eyewall of the hurricane is expected to
pass through the islands with extreme winds and an extreme wind
warning has been issued. The southern portion of the eyewall will
also move through Culebra about one and one half hours later. The
hurricane is moving west northwest at 16 mph with little
deviation. The Hurricane force winds are expected to affect the
northern USVI and portions of northern and eastern PR, while most
of the local islands are expected to observe at least tropical
storm force winds. Weather is expected to improve by Friday with
mainly locally induced showers and thunderstorms when combined
with the moisture that moved over the area as Irma continues
moving away.

&&

.AVIATION...Deteriorating conditions at all of the local terminals
expected today as major Hurricane Irma moves through the region.
MVFR ceilings and visibilities ranging from 1500 to 3000 feet and 3
to 5 miles can be expected when the core of the hurricane moves near
the local terminals. Strongest winds and worst conditions expected
at TJSJ and TJPS between 22z and 03z. At TJMZ and TJBQ, the
strongest winds and MVFR conditions should occur between 01z and 08z.
TIST is forecast to see hurricane force winds and MVFR conditions
from around 16z through 23z, and TISX should see tropical storm
force winds and MVFR ceilings and visibilities during the same time
frame. TNCM and TKPK are both experiencing the core of the hurricane
at this time.

&&

.MARINE...Hurricane Warning is in effect. Seas of over 20 feet are
expected starting this afternoon. Extremely dangerous marine
conditions are expected as seas could occasionally reach 50 feet
across the local offshore waters.

A few minutes before noon seas had reached 19 feet at the outer
buoy and 12 feet at Saint John.

&&

.HYDROLOGY...A flash flood watch continues in effect for all of
Puerto Rico and the U.S. Virgin Islands through Friday afternoon.
Rainfall will be an issue with a total storm estimate of 4 to 10
inches and isolated areas of 15 inches of rain across PR and the
northern USVI, 2 to 4 inches for Saint Croix. The hurricane is
expected to continue producing rain over the local islands even as
it moves away from the area on Thursday.

Flash flood warnings are likely to be issued within about an hour
for the northern U.S. Virgin Islands for very heavy rains.

Much of the northern two thirds of Puerto Rico has received
anywhere from one to two inches already and a few rivers have
risen significantly in northeast Puerto Rico.

&&

.PREV DISCUSSION... /issued 1005 AM AST Wed Sep 6 2017/

UPDATE...
...Hurricane conditions expected across Puerto Rico this
afternoon and tonight...

The latest forecast of Hurricane Irma has this powerful hurricane
very close or over the northern USVI by this afternoon, then
north but very close of PR later this afternoon and this evening.
The forecast track has the hurricane within 45 miles of San Juan
and within 25 miles of Saint Thomas and Saint John. The Hurricane
force winds are expected to affect the northern USVI and portions
of northern and eastern PR, while most of the local islands are
expected to observe at least tropical storm force winds. Rainfall
will be an issue as well with a total storm estimate of 4 to 10
inches of rain across PR and the northern USVI, 2 to 4 inches for
Saint Croix. The hurricane is expected to continue producing rain
over the local islands even as it moves away from the area on
Thursday. Weather is expected to improve by Friday with mainly
locally induced showers and thunderstorms when combined with the
moisture that moved over the area as Irma continues moving away.

AVIATION...Deteriorating conditions at all of the terminals
expected during the forecast period as major Hurricane Irma moves
through the region. MVFR ceilings and visibilities ranging from
1500 to 3000 feet and 3 to 5 miles can be expected when the core
of the hurricane moves near the terminals. Strongest winds and
worst conditions expected at TJSJ and TJPS between 22z and 03z. At
TJMZ and TJBQ, the strongest winds and MVFR condtions should
occur after 01z and last through the end of the forecast period.
TIST is forecast to see hurricane force winds and MVFR conditions
from around 16z through 23z, and TISX should see tropical storm
force winds and MVFR ceilings and visibilities during the same
time frame. Both TNCM and TKPK will see hurricane force winds MVFR
restrictions between 09z and 15z this morning. Wind gusts at TNCM
could exceed 140 knots when the eye passes over or near the
airport around 11-12z this morning.

MARINE...Hurricane Warning is in effect. Seas of over 20 feet are
expected starting this afternoon. Extremely dangerous marine
conditions are expected as seas could occasionally reach 50 feet
across the local offshore waters.

PREV DISCUSSION... /issued 517 AM AST Wed Sep 6 2017/

SYNOPSIS...Hurricane Irma continues to be a major hurricane and
it is approaching the local islands. Expect Tropical Storm to
Hurricane conditions to start today and continue through early
Thursday. Weather expected to improve for this weekend.

SHORT TERM...Today through Friday...

The latest forecast of Hurricane Irma has this powerful hurricane
very close to the northern USVI by this afternoon, then north of
PR this evening. The forecast track has the hurricane within 50
miles of San Juan and within 25 miles of Saint Thomas and Saint
John. The Hurricane force winds are expected to affect the
northern USVI and portions of northern and eastern PR, while most
of the local islands are expected to observe at least tropical
storm force winds. Rainfall will be an issue as well with a total
storm estimate of 4 to 10 inches of rain across PR and the
northern USVI, 2 to 4 inches for Saint Croix. The hurricane is
expected to continue producing rain over the local islands even
as it moves away from the area on Thursday. Weather is expected to
improve by Friday with mainly locally induced showers and
thunderstorms when combined with the moisture that moved over the
area as Irma continues moving away.

LONG TERM...Saturday through Thursday...

For the upcoming weekend and week, the local weather is expected
to be much quieter with relatively dry air dominating the local
area according to the latest guidance. Tropical Storm Jose is now
forecast by the National Hurricane Center to remain east of the
Leeward Islands, which would cause relatively dry air to remain
over the local islands but the marine conditions could deteriorate
if Jose starts to move west and position itself more to the north
of the local islands. Bottom line is that the weather expected for
those days should be mainly locally induced if the guidance is
correct.

AVIATION...Deteriorating conditions at all of the terminals
expected during the forecast period as major Hurricane Irma moves
through the region.  MVFR ceilings and visibilities ranging from
1500 to 3000 feet and 3 to 5 miles can be expected when the core of
the hurricane moves near the terminals.  Strongest winds and worst
conditions expected at TJSJ and TJPS between 22z and 03z.  At TJMZ
and TJBQ, the strongest winds and MVFR condtions should occur
after 01z and last through the end of the forecast period. TIST is
forecast to see hurricane force winds and MVFR conditions from
around 16z through 23z, and TISX should see tropical storm force
winds and MVFR ceilings and visibilities during the same time
frame. Both TNCM and TKPK will see hurricane force winds MVFR
restrictions between 09z and 15z this morning. Wind gusts at TNCM
could exceed 140 knots when the eye passes over or near the
airport around 11-12z this morning.

MARINE...Hurricane Warning is in effect. Seas of over 20 feet are
expected starting this afternoon. Extremely dangerous marine
conditions are expected as seas could occasionally reach 50 feet
across the local offshore waters.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  84  77  90  79 / 100 100  90  50
STT  91  81  88  81 / 100 100  30  60

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...Hurricane Warning 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.

     Flash Flood Watch through Friday afternoon 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...Hurricane Warning for St Croix-St.Thomas...St. John...and
     Adjacent Islands.

     Flash Flood Watch through Friday afternoon for St Croix-
     St.Thomas...St. John...and Adjacent Islands.

AM...Hurricane Warning for Anegada Passage Southward to 17N-Atlantic
     Waters of Puerto Rico and USVI from 10 NM to 19.5N-
     Caribbean Waters of Puerto Rico from 10 NM to 17N-Coastal
     Waters OF Northwestern Puerto Rico out 10 NM-Coastal Waters
     OF Southwestern Puerto Rico out 10 NM-Coastal Waters of
     Northern Puerto Rico out 10 NM-Coastal Waters of Northern
     USVI and Culebra out 10 NM-Coastal Waters of Southern
     Puerto Rico out 10 NM-Coastal Waters of Southern USVI
     Vieques and Eastern Puerto Rico out 10 NM-Mona Passage
     Southward to 17N.

     Flash Flood Watch through Friday afternoon for Coastal Waters OF
     Southwestern Puerto Rico out 10 NM-Coastal Waters of
     Northern USVI and Culebra out 10 NM-Coastal Waters of
     Southern Puerto Rico out 10 NM-Coastal Waters of Southern
     USVI Vieques and Eastern Puerto Rico out 10 NM.

&&

SHORT TERM...JF
LONG TERM....WS

The radar

The San Juan radar (TJUA), 93 km away, was scanning. The volume nearest the first event began at 18:41 UTC.

Open the radar archive at this moment

Event by event

25 flash flood. Local standard time, as filed.

Flash Flood, Culebra

When
September 6, 2:44 PM AST to 11:45 PM AST
Where
Culebra County, 3.84 mi E of Culebra to 1.65 mi SE of Culebra
Cause
Heavy Rain
Property damage
$500,000
Reported by
Unknown
Coordinates
18.314, -65.222

Heavy rains associated with Hurricane Irma produced flooding.

Flash Flood, Gurabo

When
September 6, 2:55 PM AST to September 7, 12:00 AM AST
Where
Gurabo County, 3.18 mi WNW of Gurabo to 2.01 mi NNW of Gurabo
Cause
Heavy Rain
Property damage
$500,000
Reported by
Unknown
Coordinates
18.294, -66.011

Heavy rainfall associated with Hurricane Irma produced flooding.

Flash Flood, Humacao

When
September 6, 2:55 PM AST to September 7, 12:00 AM AST
Where
Humacao County, 4.79 mi NNW of Humacao to 3.48 mi NNE of Humacao
Cause
Heavy Rain
Property damage
$500,000
Reported by
Unknown
Coordinates
18.198, -65.817

Heavy rains associated with Hurricane Irma produced flooding.

Flash Flood, Carolina

When
September 6, 2:55 PM AST to 8:00 PM AST
Where
Carolina County, 4.41 mi NNW of Carolina to 4.38 mi WNW of Carolina
Cause
Heavy Rain
Property damage
$250,000
Reported by
River/Stream Gage
Coordinates
18.432, -65.966

Rio Grande de Loiza flooded, inundating areas at Carolina.

Flash Flood, Canovanas

When
September 6, 2:55 PM AST to 8:00 PM AST
Where
Canovanas County, 5.82 mi NNW of Canovanas to 6.2 mi SW of Canovanas
Cause
Heavy Rain
Property damage
$500,000
Reported by
Unknown
Coordinates
18.401, -65.928

Heavy rain resulted in flash flooding.

Flash Flood, Ceiba

When
September 6, 2:55 PM AST to 8:00 PM AST
Where
Ceiba County, 2.47 mi N of Ceiba to 1.6 mi WNW of Ceiba
Cause
Heavy Rain
Property damage
$250,000
Reported by
Unknown
Coordinates
18.285, -65.637

Heavy rain resulted in flash flooding across Ceiba.

Flash Flood, Ciales

When
September 6, 3:10 PM AST to 11:15 PM AST
Where
Ciales County, 6.99 mi NNE of Ciales to 5.61 mi NE of Ciales
Cause
Heavy Rain
Property damage
$500,000
Reported by
River/Stream Gage
Coordinates
18.368, -66.467

Rio Grande de Manati went out of its banks.

Flash Flood, Cidra

When
September 6, 3:16 PM AST to September 7, 12:15 AM AST
Where
Cidra County, 3.17 mi E of Cidra to 2.56 mi NE of Cidra
Cause
Heavy Rain
Property damage
$500,000
Reported by
Unknown
Coordinates
18.166, -66.102

Heavy rainfall associated with Hurricane Irma produced flooding.

Flash Flood, Guaynabo

When
September 6, 3:16 PM AST to September 7, 12:15 AM AST
Where
Guaynabo County, 9.03 mi NW of Guaynabo to 7.45 mi NW of Guaynabo
Cause
Heavy Rain
Property damage
$500,000
Reported by
Unknown
Coordinates
18.430, -66.119

Heavy rainfall associated with Hurricane Irma produced flooding.

Flash Flood, Aguas Buenas

When
September 6, 3:16 PM AST to September 7, 12:15 AM AST
Where
Aguas Buenas County, 4.96 mi WNW of Aguas Buenas to 4.88 mi WSW of Aguas Buenas
Cause
Heavy Rain
Property damage
$177,000
Reported by
River/Stream Gage
Coordinates
18.266, -66.185

R o Grande de Lo za in Caguas, reported as flooded.

Flash Flood, Bayamon

When
September 6, 3:16 PM AST to September 7, 12:15 AM AST
Where
Bayamon County, 4.89 mi NNW of Bayamon to 4.48 mi N of Bayamon
Cause
Heavy Rain
Property damage
$250,000
Reported by
Unknown
Coordinates
18.416, -66.197

Heavy rain resulted in flash flood across Bayamon.

Flash Flood, Catano

When
September 6, 3:16 PM AST to September 7, 12:15 AM AST
Where
Catano County, 2.89 mi WNW of Catano to 2.56 mi WNW of Catano
Cause
Heavy Rain
Property damage
$250,000
Reported by
Unknown
Coordinates
18.450, -66.159

Heavy rain resulted in flash flooding across Catano.

Flash Flood, Corozal

When
September 6, 3:23 PM AST to 11:15 PM AST
Where
Corozal County, 3.97 mi N of Corozal to 3.6 mi N of Corozal
Cause
Heavy Rain
Property damage
$500,000
Reported by
Unknown
Coordinates
18.357, -66.331

Heavy rains associated with Hurricane Irma produced flooding.

Flash Flood, Florida

When
September 6, 3:23 PM AST to 11:15 PM AST
Where
Florida County, 3.44 mi NW of Florida to 2.54 mi NNW of Florida
Cause
Heavy Rain
Property damage
$500,000
Reported by
Unknown
Coordinates
18.391, -66.579

Heavy rainfall associated with Hurricane Irma produced flooding.

Flash Flood, Barceloneta

When
September 6, 3:23 PM AST to 11:15 PM AST
Where
Barceloneta County, 4.38 mi NW of Barceloneta to 4.16 mi N of Barceloneta
Cause
Heavy Rain
Property damage
$250,000
Reported by
Unknown
Coordinates
18.482, -66.589

Heavy rain resulted in flash flooding in Barceloneta.

Flash Flood, Fajardo

When
September 6, 4:18 PM AST to September 7, 12:00 AM AST
Where
Fajardo County, 2.25 mi SSE of Fajardo to 2.19 mi ENE of Fajardo
Cause
Heavy Rain
Property damage
$500,000
Reported by
River/Stream Gage
Coordinates
18.289, -65.639

Rio Fajardo went out of its banks.

Flash Flood, Hatillo

When
September 6, 4:30 PM AST to 9:30 PM AST
Where
Hatillo County, 4.46 mi NNW of Hatillo to 1.17 mi NNE of Hatillo
Cause
Heavy Rain
Property damage
$500,000
Reported by
River/Stream Gage
Coordinates
18.480, -66.824

Heavy rainfall associated with Hurricane Irma produced flooding.

Flash Flood, Jayuya

When
September 6, 4:30 PM AST to 9:30 PM AST
Where
Jayuya County, 5.37 mi N of Jayuya to 3.44 mi NE of Jayuya
Cause
Heavy Rain
Property damage
$500,000
Reported by
River/Stream Gage
Coordinates
18.278, -66.576

Heavy rainfall associated with Hurricane Irma produced flooding.

Flash Flood, Adjuntas

When
September 6, 4:30 PM AST to 9:30 PM AST
Where
Adjuntas County, 6.22 mi NNW of Adjuntas to 4.98 mi NW of Adjuntas
Cause
Heavy Rain
Property damage
$750 million
Reported by
Emergency Manager
Coordinates
18.249, -66.795

Emergency managers reported flooding in Adjuntas.

Flash Flood, Arecibo

When
September 6, 4:30 PM AST to 9:30 PM AST
Where
Arecibo County, 7.76 mi WNW of Arecibo to 9.94 mi NNE of Arecibo
Cause
Heavy Rain
Property damage
$250,000
Reported by
Unknown
Coordinates
18.482, -66.769

Heavy rain resulted in flash flooding across the area.

Flash Flood, Camuy

When
September 6, 4:30 PM AST to 9:30 PM AST
Where
Camuy County, 5.52 mi NW of Camuy to 5.23 mi N of Camuy
Cause
Heavy Rain
Property damage
$250,000
Reported by
Unknown
Coordinates
18.479, -66.907

Heavy rain resulted in flash flooding across the area.

Flash Flood, Comerio

When
September 6, 4:40 PM AST to September 7, 12:15 AM AST
Where
Comerio County, 2.93 mi N of Comerio to 1.7 mi NNE of Comerio
Cause
Heavy Rain
Property damage
$500,000
Reported by
River/Stream Gage
Coordinates
18.262, -66.212

Rio de la Plata went out of its banks.

Flash Flood, Barranquitas

When
September 6, 8:08 PM AST to September 7, 12:15 AM AST
Where
Barranquitas County, 3.51 mi NW of Barranquitas to 2.25 mi NE of Barranquitas
Cause
Heavy Rain
Property damage
$250,000
Reported by
Unknown
Coordinates
18.240, -66.353

Heavy rain resulted in flash flooding across the area.

Flash Flood, Dorad

When
September 6, 8:16 PM AST to 11:15 PM AST
Where
Dorad County, 3.64 mi NW of Dorado to 1.76 mi NE of Dorado
Cause
Heavy Rain
Property damage
$500,000
Reported by
River/Stream Gage
Coordinates
18.473, -66.313

Rio de la Plata was out of its banks.

Flash Flood, Caguas

When
September 7, 7:41 AM AST to 9:03 AM AST
Where
Caguas County, 7.57 mi NNW of Caguas to 6.98 mi N of Caguas
Cause
Heavy Rain
Property damage
$250,000
Reported by
Unknown
Coordinates
18.304, -66.066

Heavy rain resulted in flash flooding across Caguas.

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.

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

The same day elsewhere

More

Every storm in Puerto Rico in 2017Every state in 2017This day in weather historyWarnings in Puerto Rico, September 2017

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: 721841, 721846, 721848, 721887, 721939, 721940, 721837, 721838, 721845, 721853, 721943, 721944, 721840, 721844, 721948, 721843, 721847, 721849, 721850, 721954, 721955, 721839, 721956, 721842, 721942.