Flash Flooding and Heavy Snow in California, January 21, 2010

Name: Flash Flooding and Heavy Snow in California, January 21, 2010
Start: 2010-01-21T10:30
End: 2010-01-21T21:00
Location: California

January 21, 2010 · NWS VEF · 7 events in 4 counties and zones

A series of four Pacific storms pounded the Mojave Desert and southern Great Basin between January 18th and 21st with heavy rain and snow (which led to river flooding), locally high winds, and isolated severe thunderstorms.

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: $2.0 million
Crop damage: None recorded
Events: 7

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 VEF wrote it up.

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 Las Vegas, NV wrote its last area forecast discussion before the first event at Jan 21, 8:27 AM PST, 2 hours 3 minutes earlier.

Area forecast discussion, Jan 21, 8:27 AM PST, 2 hours 3 minutes before

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Hazardous weather outlook, Jan 21, 4:23 AM PST, 6 hours 7 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LAS VEGAS NV
423 AM PST THU JAN 21 2010

CAZ519-521-220800-
EASTERN SIERRA SLOPES-WHITE MOUNTAINS OF INYO COUNTY-
423 AM PST THU JAN 21 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CALIFORNIA.

.DAY ONE...TODAY AND TONIGHT

HEAVY SNOW WILL RETURN LATE THIS MORNING. A WINTER STORM WARNING
REMAINS IN EFFECT UNTIL 10 PM.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

SNOW SHOWERS WILL LINGER FRIDAY AND SATURDAY. ANOTHER STORM WILL
BRING MORE SNOW MONDAY AND TUESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER REPORTS WILL BE NEEDED TODAY.

AZZ001-003-220800-
NORTHWEST PLATEAU-NORTHWEST DESERTS-
523 AM MST THU JAN 21 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHWEST
ARIZONA.

.DAY ONE...TODAY AND TONIGHT

HEAVY RAIN AND GUSTY WINDS ARE EXPECTED THIS AFTERNOON AND
EVENING. A WIND ADVISORY WILL BE IN EFFECT FROM 11 AM THIS MORNING
TO 11 PM THIS EVENING...AND A FLOOD WATCH WILL ALSO GO INTO
EFFECT AT 11 AM.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

HEAVY RAIN WILL TAPER OFF EARLY FRIDAY MORNING...BUT THE BIG SANDY
RIVER IS EXPECTED TO CREST ABOVE FLOOD STAGE DURING THE DAY
FRIDAY. THE FLOOD WATCH WILL REMAIN IN EFFECT THROUGH FRIDAY
AFTERNOON. SHOWERS WILL LINGER FRIDAY AND SATURDAY...THEN ANOTHER
STORM WILL BRING MORE RAIN TUESDAY AND WEDNESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER REPORTS WILL BE NEEDED TODAY AND TONIGHT.

NVZ018-019-220800-
SHEEP RANGE-SPRING MOUNTAINS-
423 AM PST THU JAN 21 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHERN
NEVADA.

.DAY ONE...TODAY AND TONIGHT

HEAVY SNOW WILL RETURN AROUND MIDDAY TODAY. A WINTER STORM WARNING
REMAINS IN EFFECT THROUGH 4 AM FRIDAY MORNING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

SNOW WILL TAPER OFF EARLY FRIDAY MORNING. SNOW SHOWERS WILL LINGER
FRIDAY AND SATURDAY...THEN ANOTHER STORM WILL BRING MORE SNOW
TUESDAY AND WEDNESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER REPORTS WILL BE NEEDED TODAY AND TONIGHT.

NVZ014-015-220800-
ESMERALDA AND CENTRAL NYE COUNTY-LINCOLN COUNTY-
423 AM PST THU JAN 21 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHERN
NEVADA.

.DAY ONE...TODAY AND TONIGHT

SNOW WILL RETURN THIS AFTERNOON. A WINTER WEATHER ADVISORY REMAINS
IN EFFECT UNTIL 4 AM FRIDAY MORNING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

SNOW WILL TAPER OFF EARLY FRIDAY MORNING. SNOW SHOWERS WILL LINGER
FRIDAY AND SATURDAY...THEN ANOTHER STORM WILL BRING MORE RAIN AND
SNOW TUESDAY AND WEDNESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER REPORTS WILL BE NEEDED TODAY AND TONIGHT.

NVZ016-220800-
NORTHEAST CLARK COUNTY-
423 AM PST THU JAN 21 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHERN
NEVADA.

.DAY ONE...TODAY AND TONIGHT

HEAVY RAIN IS EXPECTED THIS AFTERNOON AND EVENING. A FLOOD WATCH
WILL GO INTO EFFECT AT 10 AM.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

HEAVY RAIN WILL TAPER OFF EARLY FRIDAY MORNING...BUT THE MUDDY
RIVER IS EXPECTED TO CREST NEAR FLOOD STAGE FRIDAY AFTERNOON. THE
FLOOD WATCH WILL REMAIN IN EFFECT THROUGH FRIDAY AFTERNOON.
SHOWERS WILL LINGER FRIDAY AND SATURDAY...THEN ANOTHER STORM WILL
BRING MORE RAIN TUESDAY AND WEDNESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER REPORTS WILL BE NEEDED TODAY AND TONIGHT.

AZZ002-036-CAZ520-522>527-NVZ017-020>022-220800-
LOWER COLORADO RIVER VALLEY-LAKE MEAD NATIONAL RECREATION AREA-
OWENS VALLEY-DEATH VALLEY NATIONAL PARK-WESTERN MOJAVE DESERT-
EASTERN MOJAVE DESERT-MORONGO BASIN-CADIZ BASIN-
SAN BERNARDINO COUNTY-UPPER COLORADO RIVER VALLEY-
WESTERN CLARK AND SOUTHERN NYE COUNTY-LAS VEGAS VALLEY-
SOUTHERN CLARK COUNTY-
423 AM PST THU JAN 21 2010 /523 AM MST THU JAN 21 2010/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHWEST
ARIZONA...CALIFORNIA AND SOUTHERN NEVADA.

.DAY ONE...TODAY AND TONIGHT

VALLEY RAIN AND MOUNTAIN SNOW WILL OVERSPREAD THE AREA TODAY AND
CONTINUE THROUGH THIS EVENING BEFORE TAPERING OFF TO SHOWERS
OVERNIGHT. LOCALLY HEAVY RAIN AND SNOW WILL BE POSSIBLE.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

SHOWERS WILL LINGER FRIDAY AND SATURDAY...THEN ANOTHER STORM WILL
BRING MORE RAIN AND SNOW TUESDAY AND WEDNESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER REPORTS WILL BE NEEDED TODAY AND TONIGHT.

MORGAN

In the hours before

Local storm report, Jan 21, 7:34 AM PST, 2 hours 56 minutes before

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Local storm report, Jan 21, 7:49 AM PST, 2 hours 41 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LAS VEGAS NV
749 AM PST THU JAN 21 2010

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

1030 PM     HEAVY SNOW       9 W MOUNTAIN SPRINGS RA 36.03N 115.68W
01/20/2010  M15.0 INCH       CLARK              NV   PUBLIC

            LAS VEGAS SKI AND SNOWBOARD RESORT 15.0 INCHES OF NEW
            SNOW AT AN ELEVATION OF 8852 FEET. THE SNOW LIKELY BEGAN
            AROUND NOON WEDNESDAY AND ENDED AROUND 1030 PM. START AND
            END TIMES ARE ESTIMATED BASED ON WEB CAMS...RADAR AND
            SATELLITE.

&&

STACHELSKI

Local storm report, Jan 21, 7:52 AM PST, 2 hours 38 minutes before

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The radar

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

Open the radar archive at this moment

Event by event

5 flash flood, 1 heavy snow, 1 strong wind. Local standard time, as filed.

Heavy Snow, Owens Valley

When: January 21, 10:30 AM PST to 9:00 PM PST
Where: Owens Valley forecast zone
Reported by: Law Enforcement

The sheriff's office measured 6.5 inches of snow in Independence (4000').

Flash Flood, San Bernardino

When: January 21, 11:33 AM PST to 3:00 PM PST
Where: San Bernardino County, 56.33 mi SW of Tecopa to 56.87 mi SW of Tecopa
Cause: Heavy Rain
Reported by: Other Federal Agency
Coordinates: 35.206, -116.834

Mud and debris covered most roads in Fort Irwin.

Flash Flood, San Bernardino

When: January 21, 2:48 PM PST to 3:48 PM PST
Where: San Bernardino County, Joshua Tree to 1.45 mi WNW of Joshua Tree
Cause: Heavy Rain
Reported by: Trained Spotter
Coordinates: 34.130, -116.320

Water and debris were on several roads in the Joshua Tree area. An elderly care center was also flooded.

Flash Flood, Inyo

When: January 21, 3:14 PM PST to 6:14 PM PST
Where: Inyo County, 8.12 mi SW of Ryan to 6.53 mi SSW of Ryan
Cause: Heavy Rain
Reported by: Law Enforcement
Coordinates: 36.248, -116.786

Badwater Road was closed at Badwater Basin due to flooding.

Flash Flood, San Bernardino

When: January 21, 3:24 PM PST to 6:24 PM PST
Where: San Bernardino County, 2.38 mi WSW of Needles to 2.57 mi SSW of (Eed)needles Arpt
Cause: Heavy Rain
Property damage: $2.0 million
Reported by: Law Enforcement
Coordinates: 34.818, -114.640

U.S. Highway 95 was closed south of Interstate 40 due to flooding and roadway damage. Portions of the highway were closed for a week.

Flash Flood, San Bernardino

When: January 21, 5:31 PM PST to 6:31 PM PST
Where: San Bernardino County, 1.8 mi ENE of Yucca Vly Arpt to 1.96 mi NNE of Yucca Vly Arpt
Cause: Heavy Rain
Reported by: Trained Spotter
Coordinates: 34.140, -116.371

A stretch of Yucca Mesa Road was closed due to flooding.

Strong Wind, Morongo Basin

When: January 21, 5:31 PM PST
Where: Morongo Basin forecast zone
Measured: 43 kt (49 mph) estimated gust
Property damage: $3,000
Reported by: Trained Spotter
Coordinates: 34.841, -116.178 (the zone’s center; the record gives no point)

Strong winds damaged a home's roof.

What these are

Heavy Snow: Snowfall reaching the local warning threshold without the other hazards of a winter storm.
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.
Strong Wind: Non-thunderstorm winds below high wind criteria that nonetheless caused damage or casualties.

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

The same day elsewhere

Every storm in California in 2010 Every state in 2010 This day in weather history Warnings in California, January 2010

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 2026-10-01. Each event’s entry at NCEI: 206937, 206929, 206930, 206931, 206933, 206935, 206936.