Flooding in Puerto Rico, December 4, 2001

Name: Flooding in Puerto Rico, December 4, 2001
Start: 2001-12-04T21:00
End: 2001-12-04T23:00
Location: Puerto Rico

December 4, 2001 · NWS SJU · 2 events in 2 counties and zones

Heavy rains caused urban flooding at low and poor drainage areas in parts of Carolina, Loiza, San Juan and Guaynabo. Puerto Nuevo River went out of its banks in Guaynabo.

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 happened

The episode as NWS SJU wrote it up.

Heavy rains caused urban flooding at low and poor drainage areas in parts of Carolina, Loiza, San Juan and Guaynabo. Puerto Nuevo River went out of its banks in Guaynabo.

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 Dec 4, 4:00 PM AST, 5 hours earlier.

Area forecast discussion, Dec 4, 4:00 PM AST, 5 hours before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
400 PM AST TUE DEC 4 2001

BASED ON SATELLITE AND ANALYSIS...INVERTED LOW LEVEL TROUGH
INDIRECTLY ASSOCIATED WITH OLGA WAS ACTUALLY LOCATED ACROSS THE U.S.
VIRGIN ISLANDS THIS MORING AND AFTERNOON. NORTHEASTERLY WINDS AHEAD
OF TROF AFFECTING THE NORTHCOAST OF PUERTO RICO THIS AFTERNOON. TROF
NOT EXPECTED TO MOVE INTO THE AREA BUT WILL FILL AS TD OLGA
CONTINUES TO DIE A SLOW DEATH. BAND OF SHOWERS MOVING ACROSS PUERTO
RICO AROUND NOON WILL CONTINUE TO MOVE WEST THROUGH MIDNIGHT. HAVE
LEFT HIGH POPS FOR EASTERN PR WITH DIMINISHING SHOWERS AFTER
MIDNIGHT. THIS DOES NOT SAY WE WILL NOT GET SHOWERS AFTERNOON
MIDNIGHT BUT THEY SHOULD NOT BE AS STRONG AS WHAT IS CURRENTLY
ADVECTING ACROSS THE AREA. WILL GRADUALLY DECREASE DIURNAL SHOWERS
THROUGH NEXT 48 HOURS WITH SHOWERS MAINLY LIKELY ACROSS THE NORTHERN
COASTS OF PUERTO RICO AT NIGHT DUE TO WINDS BECOMING STRONGER FROM
THE NORTHEAST BRING IN BATCHES OF MOISTURE...SIMILIAR TO LAST WEEK.
NEXT BOUNDARY...WHETHER AN OLD FRONTAL BOUNDARY...SHEAR LINE OR
DISCONTIUITY SHOULD APPROACH 20N LATE THURSDAY NIGHT OR FRIDAY.

PRELIMINARY NUMBERS...
SJU BB 072/086 072/085 073 07444
STT BB 075/086 075/085 074 07444=

.SJU...
.PR...NONE.
.VI...NONE.

TIRADO

WRITTEN TEXT FORECASTS (IN ENGLISH OR SPANISH)...SATELLITE IMAGERY
...DOPPLER RADAR DATA...AND A VIRTUAL LIBRARY OF WEATHER INFORMATION
CAN BE FOUND AT THE NWS SAN JUAN WEB SITE AT:

HTTP://WWW.SRH.NOAA.GOV/SJU (ALL LOWER CASE).

Event by event

2 flood. Local standard time, as filed.

Flood, San Juan and Vicinity

When: December 4, 9:00 PM AST to 11:00 PM AST
Where: San Juan and Vicinity County, Countywide
Reported by: EMERGENCY MANAGER

Flood, Northeast

When: December 4, 9:00 PM AST to 11:00 PM AST
Where: Northeast County, West Portion
Reported by: EMERGENCY MANAGER

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.

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

The same day elsewhere

Every storm in Puerto Rico in 2001 Every state in 2001 This day in weather history Warnings in Puerto Rico, December 2001

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: 5275363, 5275364.