California, 2003

Flash Flooding and Hail in California, November 12, 2003

November 12, 2003 · NWS LOX · 5 events in 1 county or zone

A large and powerful thunderstorm produced heavy rain in excess of 5 inches in less than two hours, flash flooding and hail across South Central Los Angeles county. Hail accumulations in the area were over 5 inches.

Where it happened

Every event with a place to put it; 4 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
$3.5 million
Crop damage
None recorded
Events
5

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 LOX wrote it up.

A large and powerful thunderstorm produced heavy rain in excess of 5 inches in less than two hours, flash flooding and hail across South Central Los Angeles county. Hail accumulations in the area were over 5 inches. Numerous intersections were flooded with several feet of water, stranding thousands of motorists during rush hour. Over 130 homes and businesses experienced significant damage due to flooding and hail. Damage was so significant that South Central Los Angeles county was declared a state disaster area. Overall, damage estimates were around $3.5 million for the area.

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.

Hazardous weather outlook, Nov 12, 8:15 AM PST, 8 hours 11 minutes before
CAZ034>041-044>047-051>054-059-087-088-130200-

HAZARDOUS WEATHER OUTLOOK...CORRECTION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
815 AM PST WED NOV 12 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHWESTERN CALIFORNIA.

.DAY ONE...TODAY

NUMEROUS SHOWERS AND THUNDERSTORMS WILL OCCUR TODAY. THERE IS A
STRONG POTENTIAL FOR FLASH FLOODING IN THE BURN AREAS DUE TO THE
HIGH RAINFALL RATES ASSOCIATED WITH THUNDERSTORMS. A FLASH FLOOD
WATCH HAS BEEN ISSUED FOR THE BURN AREAS.

DANGEROUS LIGHTNING AND SMALL HAIL WILL BE POSSIBLE TODAY ANYWHERE
AND AT ANY TIME.

THE THUNDERSTORMS AND SHOWERS WILL DIMINISH OVERNIGHT.

THE SNOW LEVEL WILL LOWER TO BETWEEN 5000 AND 5500 FEET BY LATE THIS
AFTERNOON. SNOW WILL FALL THROUGH THE NIGHT. THE GREATEST
ACCUMULATIONS WILL BE OVER THE NORTHERN MOUNTAINS. 4 TO 8 INCHES OF
SNOW IS FORECAST OVER THE NORTHERN MOUNTAINS WHILE 2 TO 4 INCHES IS
FORECAST ELSEWHERE IN THE MOUNTAINS.

MOUNTAIN WINDS WILL BLOW FROM THE EAST TODAY FROM 20 TO 30 MPH WITH
GUSTS TO 40 MPH.

* FLOOD WATCH................SEE WGUS66 KLOX - FFALOX FOR DETAILS *

* WINTER WEATHER ADVISORY....SEE WWUS46 KLOX - WSWLOX FOR DETAILS *

.DAYS TWO THROUGH SEVEN... THURSDAY THROUGH TUESDAY

SNOW SHOWERS OVER THE MOUNTAINS WILL LINGER THROUGH THURSDAY
MORNING...OTHERWISE HAZARDOUS WEATHER IS NOT EXPECTED DURING THE
PERIOD.

* WINTER WEATHER ADVISORY....SEE WWUS46 KLOX - WSWLOX FOR DETAILS *

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

RORKE/SWEET

The radar

The Santa Ana Mts radar (KSOX), 71 km away, was scanning. The volume nearest the first event began at 01:00 UTC.

Open the radar archive at this moment

Event by event

4 flash flood, 1 hail. Local standard time, as filed.

Flash Flood, Los Angeles

When
November 12, 4:26 PM PST to 9:00 PM PST
Where
Los Angeles County, Watts
Reported by
NEWSPAPER
Coordinates
34.198, -118.261 (the zone’s center; the record gives no point)

Flash Flood, Los Angeles

When
November 12, 4:59 PM PST to 9:00 PM PST
Where
Los Angeles County, Compton
Reported by
NEWSPAPER
Coordinates
34.198, -118.261 (the zone’s center; the record gives no point)

Hail, Los Angeles

When
November 12, 5:00 PM PST to 9:00 PM PST
Where
Los Angeles County, Compton
Measured
0.5 in hail
Property damage
$3.5 million
Reported by
NEWSPAPER
Coordinates
33.883, -118.217

Flash Flood, Los Angeles

When
November 12, 5:51 PM PST to 9:00 PM PST
Where
Los Angeles County, Compton
Reported by
NEWSPAPER
Coordinates
34.198, -118.261 (the zone’s center; the record gives no point)

Flash Flood, Los Angeles

When
November 12, 8:36 PM PST to 9:00 PM PST
Where
Los Angeles County, Watts
Reported by
NEWSPAPER
Coordinates
34.198, -118.261 (the zone’s center; the record gives no point)

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.
Hail
Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.

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

The same day elsewhere

More

Every storm in California in 2003Every state in 2003This day in weather historyWarnings in California, November 2003

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: 5331119, 5331120, 5331118, 5331121, 5331122.