Debris Flow in Puerto Rico, May 15, 2004

Name: Debris Flow in Puerto Rico, May 15, 2004
Start: 2004-05-15T16:44
End: 2004-05-15T16:44
Location: Puerto Rico

May 15, 2004 · NWS SJU · 1 event in 1 county or zone

1 debris flow, as filed by the National Weather Service.

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 1

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 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 15, 3:50 PM AST, 54 minutes earlier.

Area forecast discussion, May 15, 3:50 PM AST, 54 minutes before

PUERTO RICO AND U.S. VIRGIN ISLANDS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
350 PM AST SAT MAY 15 2004

.DISCUSSION...
CURRENT SCENARIO IS VERY SIMILAR TO YESTERDAY WITH MAX RAINFALL
ACROSS PORTIONS OF THE EAST AND INLAND SAN JUAN METRO AREA AND THE
WESTERN INTERIOR EXTENDING TO THE WEST TO SOUTHWEST COASTS OF PR.
MAJOR FLOOD PROBLEMS ACROSS PORTIONS OF SAN JUAN METRO WHERE AROUND
4 INCHES FELL...ESPECIALLY OVER RIO PIEDRAS AND RIO GUAYNABO.

LOOKING AT CURRENT SATELLITE...IT SHOWS STRONG NE COMPONENT TO FLOW
AT LOW LEVELS UPSTREAM IN THE LEEWARD ISLANDS AND RELATIVELY DRIER
AIR. BELIEVE CURRENT SITUATION IS JUST AN ENHACEMENT OF LOCAL
EFFECTS CAUSED BY STRONG JET DYNAMICS AT UPPER LEVELS AND HIGH
MOISTURE LEVELS IN THE ATMOSPHERE. WITH THIS IN MIND...BELIEVE
SHOWERS WILL BE LOCATED IN DIURNALLY FAVORED AREAS TONIGHT AND
SUNDAY WHICH IS DEPENDANT ON LOW LEVEL FLOW AND MOISTURE. THEREFORE
EXPECT MOST SHOWER ACTIVITY IN COASTAL WATERS AND EASTERN HALF OF
FORECAST AREA OVERNIGHT AND THE CONVECTION OUT WEST SHOULD DIE OUT
AFTER SUNSET THIS EVENING. MODELS SHOW INCREASE IN MOISTURE TOWARD
MORNING...BUT KEEP MOST OF MOISTURE TO OUR SOUTH OVER NEXT FEW DAYS.
BY SUNDAY NIGHT LOOKS LIKE WINDS WILL SHIFT TO MORE NE HELPING TO
BRING IN RELATIVELY DRIER AIR. THEREFORE OVERALL FORECAST LOOKS LIKE
BETTER WEATHER FOR MONDAY INTO TUESDAY.

.PRELIMINARY POINT TEMPS/POPS...
SJU  82  75  83  75 /  70 100 100 100
STT  81  74  82  74 /  50 100 100 100

&&

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

&&

RGZ

Hazardous weather outlook, May 15, 6:10 AM AST, 10 hours 34 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN JUAN PR
610 AM AST SAT MAY 15 2004

PRZ001>013-AMZ710>750-161000-
610 AM AST SAT MAY 15 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PUERTO RICO.

.TODAY...THE LOCAL AIRMASS STILL VERY MOIST AND UNSTABLE. RAINFALL
AMOUNTS EVEN IN SMALL QUANTITIES MAY BE SIGNIFICANT SINCE SOILS ARE
VERY SATURATED ESPECIALLY OVER THE NORTH HALF AND EAST SECTIONS.
RIVERS AND STREAMS LEVELS ARE VERY HIGH AND THESE WILL FLOOD WITH
LESSER AMOUNTS OF RAIN OVER THEIR BASINS. LANDSLIDES ARE LIKELY OVER
STEEP TERRAIN. HEAVY RAIN IS EXPECTED ONCE AGAIN TODAY RESULTING IN
FLOODING.

MARINE CONDITIONS WILL CONTINUE ROUGH AND CHOPPY ALONG THE ATLANTIC
AND CARIBBEAN WATERS WITH GOOD CHANCES FOR WATERSPOUTS TO DEVELOP
TOGETHER WITH VERY HEAVY DOWNPOURS AND REDUCED VISIBILITIES.

.SPOTTER CALL TO ACTION STATEMENT...
SPOTTER ACTIVATION MAY BE REQUIRED.

.DAYS TWO THROUGH SEVEN...

ALTHOUGH THE POTENTIAL FOR HEAVY PRECIPITATION AND CHANCES FOR FLASH
FLOODING WILL REMAIN HIGH THROUGH THE WEEK NOW SUNDAY SEEMS TO BE
THE DAY WITH MORE SEVERE WEATHER. THIS INCLUDES VIEQUES AND CULEBRA.
WEATHER THIS DAY MAY BECOME SEVERE. LANDSLIDES ARE LIKELY OVER STEEP
TERRAIN.

A MODERATE TO FRESH WIND FLOW AND CHOPPY SEAS WILL PREVAIL ACROSS
THE LOCAL WATERS WITH GOOD CHANCES FOR WATERSPOUTS....HEAVY
DOWNPOURS AND REDUCED VISIBILITIES.

VIZ001-002-AMZ710>730-161000-
610 AM AST SAT MAY 15 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE U.S. VIRGIN ISLANDS.

.TODAY...CONTINUOUS MODERATE TO HEAVY PASSING SHOWERS WILL LEAD TO
URBAN FLOODING AND POSSIBLE FLASH FLOODING.

.SPOTTER CALL TO ACTION STATEMENT...
SPOTTER ACTIVATION IS NOT ANTICIPATED.

.DAYS TWO THROUGH SEVEN...

CHANCES FOR PRECIPITATION WILL REMAIN HIGH BUT SUNDAY WEATHER
CONDITIONS MAY BECOME SEVERE. OVER THE WATERS THERE ARE GOOD CHANCES
FOR WATERSPOUT DEVELOPMENT AND VERY HEAVY DOWNPOURS.

STAY TUNED TO NOAA WEATHER RADIO AND OTHER LOCAL MEDIA FOR FURTHER
DETAILS OR UPDATES.

FOR ADDITIONAL INFORMATION...VISIT THE NATIONAL WEATHER SERVICE WEB
SITE FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS AT (ALL LOWERCASE
LETTERS): HTTP://WWW.SRH.NOAA.GOV/SJU.

RIVERA

In the hours before

Local storm report, May 15, 11:44 AM AST, 5 hours before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SAN JUAN PR
1144 AM AST SAT MAY 15 2004

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

1139 AM     FLOOD        GUAYNABO                18.39N 66.11W
05/15/2004               GUAYNABO           PR   NWS EMPLOYEE

            UP TO A FOOT OF WATER ON THE ROADWAYS. HEAVY RAIN
            CONTINUES.

&&

RGZ

Local storm report, May 15, 12:00 PM AST, 4 hours 44 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SAN JUAN PR
1200 PM AST SAT MAY 15 2004

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

1200 PM     FLASH FLOOD      SAN JUAN                18.41N 66.06W
05/15/2004                   SAN JUAN           PR   EMERGENCY MNGR

            A REPORT OF A HOUSE FLOODED IN THE URBANIZATION OF SAN
            FRANCISCO IN RIO PIEDRAS. ANOTHER REPORT OF THE SMALL
            RIVER JOSEFINA OUT OF ITS BANKS WHICH FLOODED PORTIONS OF
            AVENUE DE DIEGO.

&&

RGZ

Local storm report, May 15, 12:38 PM AST, 4 hours 6 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SAN JUAN PR
1238 PM AST SAT MAY 15 2004

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

1232 PM     FLOOD            E GUAYNABO              18.39N 66.11W
05/15/2004                   GUAYNABO           PR   EMERGENCY MNGR

            TRIBUTARY OF THE RIO GUAYNABO IS OUT OF ITS BANKS CAUSING
            FLOODING OF ROADWAY EAST OF THE MARTINEZ NADAL HWY.

&&

RAM

Local storm report, May 15, 4:42 PM AST, 2 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SAN JUAN PR
442 PM AST SAT MAY 15 2004

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

0430 PM     FLASH FLOOD      5 S SAN JUAN            18.34N 66.06W
05/15/2004                   SAN JUAN           PR   EMERGENCY MNGR

            A MUDSLIDE DROPPED OVER ROUTE 842 IN CAIMITO

&&

WLS

Event by event

1 debris flow. Local standard time, as filed.

Debris Flow, San Juan and Vicinity

When: May 15, 4:44 PM AST
Where: San Juan and Vicinity forecast zone
Reported by: EMERGENCY MANAGER

A landslide was reported along road 842 in Barrio Caimito.

What these are

Debris Flow: A fast-moving slurry of mud, rock and debris, usually on a slope soaked by heavy rain or stripped by a fire.

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

The same day elsewhere

Every storm in Puerto Rico in 2004 Every state in 2004 This day in weather history Warnings in Puerto Rico, May 2004

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: 5398799.