Debris Flow and Heavy Rain in Puerto Rico, April 26, 2004

Name: Debris Flow and Heavy Rain in Puerto Rico, April 26, 2004
Start: 2004-04-26T16:30
End: 2004-04-26T16:30
Location: Puerto Rico

April 26, 2004 · NWS SJU · 2 events in 1 county or zone

1 heavy rain, 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: 2

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 Apr 26, 3:30 PM AST, 1 hour earlier.

Area forecast discussion, Apr 26, 3:30 PM AST, 1 hour before

PUERTO RICO AND U.S. VIRGIN ISLANDS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
330 PM AST MON APR 26 2004

.DISCUSSION...SCATTERED TO NUMEROUS SHOWERS AFFECTED DIFFERENT
PORTIONS OF PUERTO RICO THIS AFTERNOON.  A CU LINE DEVELOP OVER EL
YUNQUE AND MOVE OVER THE SAN JUAN METRO AREA WITH RAINFALL
ACCUMULATIONS OF AROUND 3 INCHES OVER THE MUNICIPALITIES OF
CATANO...TOA BAJA AND BAYAMON. ANOTHER BATCH OF NUMEROUS SHOWERS
DEVELOPED OVER THE WESTERN INTERIOR SECTIONS OF PUERTO RICO. AT THIS
HOUR THE RADAR HOURLY PRECIPITATION ESTIMATES SHOWED OVER 4 INCHES
OF RAIN AROUND THIS AREA. THESE SHOWERS ARE EXPECTED TO DISSIPATE OR
MOVE WEST AWAY OF THIS AREA.

ON TUESDAY...THE THROUGH JUST NORTH WEST OF THE ISLAND WILL BE A
MAJOR INFLUENCE FOR TOMORROW WEATHER. THIS FEATURE WILL ENHANCE
AFTERNOON SHOWERS...SIMILAR TO WHAT WE HAD TODAY EVEN IF MODELS A RE
SHOWING A SLIGHT DECREASED ON THE MOISTURE. WINDS ARE EXPECTED TO
INCREASE TOMORROW AND THEY WILL STAY BETWEEN 15 TO 20 MPH THROUGH
THE END OF THE WEEK. HIGHER GUST COULD BE EXPECTED ALONG THE COAST

&&

.SYNOPSIS...A LOW LEVEL TROUGH WITH WEAK REFLECTION AT THE SURFACE
WAS LOCATED ACROSS THE MONA PASSAGE AND ADJACENT REGIONAL WATERS
THIS AFTERNOON...AND WILL CONTINUE TO MOVE WESTWARD THROUGH THIS
EVENING...BRINGING INCREASING WIND...SHOWERS...AND A FEW SQUALLS TO
THE LOCAL AREA. HIGH PRESSURE CENTERED NEAR BERMUDA WILL SHIFT
EAST INTO THE CENTRAL ATLANTIC TONIGHT THROUGH THURSDAY...AND BUILD
ACROSS THE LOCAL REGION.

&&

.MARINE...WINDS ARE EXPECTED TO INCREASE PRODUCING CHOPPY SEAS
THROUGH AT LEAST THE END OF THE WEEK. THEREFORE SMALL CRAFT
OPERATORS SHOULD EXERCISE CAUTIONS OVER THE ATLANTIC AND CARIBBEAN
WATERS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  74  87  74  85 /  30  50  50  20
STT  74  84  74  84 /  30  50  50  10

&&

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

&&

10

Hazardous weather outlook, Apr 26, 6:00 AM AST, 10 hours 30 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN JUAN PR
600 AM AST MON APR 26 2004

PRZ001>013-AMZ710>750-271000-
600 AM AST MON APR 26 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PUERTO RICO.

.TODAY AND TONIGHT...A WEAK LOW LEVEL TROUGH IN THE EASTERLY WIND
FLOW WITH CONTINUE ACROSS THE LOCAL REGION TODAY THROUGH TONIGHT.
THIS WILL ASSIST IN THE DEVELOPMENT OF LIGHT TO MODERATE EARLY
MORNING SHOWERS. SCATTERED AREAS OF HEAVIER SHOWERS WILL FOLLOW
DURING THE AFTERNOON MAINLY ACROSS THE INTERIOR AND WEST SECTIONS OF
PUERTO RICO. THIS WILL RESULT IN LOCALIZED MODERATE TO HEAVY RAIN.
THEREFORE...URBAN FLOODING MAY OCCUR OVER ISOLATED LOCALITIES OF THE
INTERIOR AND WEST PUERTO RICO.

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

.TUESDAY THROUGH SUNDAY...LOW LEVEL TROUGH WILL CONTINUE TO MOVE
ACROSS THE LOCAL THROUGH TUESDAY. ON WEDNESDAY...HIGH PRESSURE RIDGE
WILL THEN BUILD ACROSS THE REGION AND BRING AN INCREASE IN THE LOCAL
WIND FLOW. THIS WILL BRING ABOUT AN INCREASE IN MAINLY THE OFF SHORE
SEA CONDITIONS. AS A RESULT...VERY CHOPPY MARINE CONDITIONS CAN BE
EXPECTED THE REST OF THE WEEK. NO SIGNIFICANT WEATHER HAZARDS
EXPECTED THEREAFTER.

VIZ001-002-AMZ710>730-271000-
600 AM AST MON APR 26 2004

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

.TODAY AND TONIGHT...A WEAK LOW LEVEL TROUGH IN THE EASTERLY WIND
FLOW WITH CONTINUE TO MOVE WEST ACROSS THE LOCAL ISLANDS TODAY
THROUGH TONIGHT. SCATTERED LIGHT TO MODERATE PASSING SHOWERS ARE
EXPECTED...HOWEVER FLASH FLOOD CONDITIONS ARE NOT ANTICIPATED.

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

.TUESDAY THROUGH SUNDAY..LOW LEVEL TROUGH WILL EXIT THESE ISLANDS ON
TUESDAY. ON WEDNESDAY...HIGH PRESSURE RIDGE WILL THEN BUILD ACROSS
THE REGION AND BRING AN INCREASE IN THE LOCAL WIND FLOW. THIS WILL
BRING ABOUT AN INCREASE IN MAINLY THE OFF SHORE SEA CONDITIONS. AS A
RESULT...VERY CHOPPY MARINE CONDITIONS CAN BE EXPECTED THE REST OF
THE WEEK. NO SIGNIFICANT WEATHER HAZARDS EXPECTED THEREAFTER.

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.

In the hours before

Local storm report, Apr 26, 1:45 PM AST, 2 hours 45 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SAN JUAN PR
145 PM AST MON APR 26 2004

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

0130 PM     FLASH FLOOD      TOA BAJA                18.44N 66.25W
04/26/2004                   TOA BAJA           PR   EMERGENCY MNGR

            HIGH SCHOOL AND 2 HOUSES FLOODED

&&

PC

Event by event

1 heavy rain, 1 debris flow. Local standard time, as filed.

Heavy Rain, Western Interior

When: April 26, 4:30 PM AST
Where: Western Interior County, Utuado
Reported by: EMERGENCY MANAGER

A small stream was reported out of its banks along road 10 from Utuado to Adjuntas in front of Roman Hardware Store.

Debris Flow, Western Interior

When: April 26, 4:30 PM AST
Where: Western Interior forecast zone
Reported by: EMERGENCY MANAGER

Landslide was reported along road 603 at Barrio Guaynico in Utuado.

What these are

Heavy Rain: Rainfall totals unusual for the place and season that did not produce a flood.
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, April 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: 5390257, 5390258.