Flood in California, May 20, 2002

Name: Flood in California, May 20, 2002
Start: 2002-05-20T09:02
End: 2002-05-20T09:50
Location: California

May 20, 2002 · NWS SGX · 1 event in 1 county or zone

A quarter inch of rain in less than an hour caused Carbon Creek to overflow it's banks, leading to street flooding at the intersection of Rose St. and Buena Vista Avenue.

Where it happened

Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. 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: 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 happened

The episode as NWS SGX wrote it up.

A quarter inch of rain in less than an hour caused Carbon Creek to overflow it's banks, leading to street flooding at the intersection of Rose St. and Buena Vista Avenue.

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 Diego, CA wrote its last area forecast discussion before the first event at May 20, 8:30 AM PST, 32 minutes earlier.

Area forecast discussion, May 20, 8:30 AM PST, 32 minutes before

EXTREME SOUTHWESTERN CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
930 AM PDT MON MAY 20 2002

.SYNOPSIS...A DEEP MARINE LAYER AND STRONG ONSHORE FLOW WILL MAINTAIN
LOW CLOUDS WEST OF THE MOUNTAINS WITH ISOLATED LIGHT SHOWERS CONTINUING
INTO TUESDAY MORNING. SNOW FLURRIES ARE EXPECTED ABOVE ABOUT 6000 FEET.
THE SHOWERS ARE EXPECTED TO MOVE EAST BY MIDDAY TUESDAY...FOLLOWED BY A
WARMING TREND THAT CONTINUES INTO THE WEEKEND.

.DISCUSSION...A WEAK COLD FRONT CONTINUES TO SLOWLY PUSH EAST OVER OUR
AREA...WITH SOME LIGHT SHOWERS JUST ABOUT EVERYWHERE.  THIS SHOULD BE
THE CASE FOR THE NEXT 24 HOURS AS THE FRONT SLOWLY MOVES EAST.

COOLING ALOFT SHOULD WEAKEN THE INVERSION SIGNIFICANTLY BY TUESDAY
AFTERNOON...BUT UNTIL THEN THE CLOUDS AND LIGHT SHOWERS SHOULD HANG
AROUND. WARMING IS EXPECTED WEDNESDAY INTO THE WEEKEND AS THICKNESSES
CLIMB...BUT WEAK TROUGHS SWEEPING BY TO THE NORTH WILL KEEP CONDITIONS
FROM DEVIATING MUCH FROM NORMAL DURING THE LATTER PART OF THE WEEK. I
COULD ADJUST THE WORDING A BIT IN THE CURRENT PERIOD OF THE ZONES...BUT
THE MEANING WOULD NOT CHANGE...THEREFORE I WILL NOT ADJUST THE CURRENT
ZONES.

.SAN...SMALL CRAFT ADVISORY FOR OUTER WATERS...SEE LAXCWFSGX.

SMALL

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

1 flood. Local standard time, as filed.

Flood, Orange

When: May 20, 9:02 AM PST to 9:50 AM PST
Where: Orange County, 1 mi SE of Placentia
Reported by: TRAINED SPOTTER
Coordinates: 33.677, -117.776 (the zone’s center; the record gives no point)

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 California in 2002 Every state in 2002 This day in weather history Warnings in California, May 2002

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: 5291435.