Heavy Snow and Winter Weather in California, April 4 to 5, 2010

Name: Heavy Snow and Winter Weather in California, April 4 to 5, 2010
Start: 2010-04-04T15:00
End: 2010-04-05T09:00
Location: California

April 4 to 5, 2010 · NWS REV · 3 events in 3 counties and zones

A strong system dropped out of the Gulf of Alaska and produced heavy snow, especially west of highway 395 in Mono County and near the Sierra crest for the Lake Tahoe area.

Where it happened

Every event with a place to put it; 3 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: 3

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 REV wrote it up.

A strong system dropped out of the Gulf of Alaska and produced heavy snow, especially west of highway 395 in Mono County and near the Sierra crest for the Lake Tahoe 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, Apr 3, 3:08 PM PST, 23 hours 52 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

2 heavy snow, 1 winter weather. Local standard time, as filed.

Winter Weather, Lassen/Eastern Plumas/Eastern Sierra

When: April 4, 3:00 PM PST to April 5, 2:00 AM PST
Where: Lassen/Eastern Plumas/Eastern Sierra forecast zone
Reported by: Public
Coordinates: 40.086, -120.650 (the zone’s center; the record gives no point)

Accumulations for this event were not widespread over the forecast zone, with significant accumulations mainly well west of highway 395 and south of highway 36 with much less snowfall (less than 2 inches) elsewhere. There were some chain controls for the higher terrain of highway 89 in southern Sierra County. Here are some of the higher snowfall totals: 10 inches at the Independence Creek SNOTEL and 7 inches at the Portola CO-OP.

Heavy Snow, Greater Lake Tahoe Area

When: April 4, 4:00 PM PST to April 5, 6:00 AM PST
Where: Greater Lake Tahoe Area forecast zone
Reported by: Public
Coordinates: 38.935, -120.458 (the zone’s center; the record gives no point)

A widespread 6 to 10 inch snowfall was reported around the Lake Tahoe Basin, with 10 to 16 inches common west of highway 89 and near the Sierra crest.

Heavy Snow, Mono

When: April 4, 5:00 PM PST to April 5, 9:00 AM PST
Where: Mono forecast zone
Reported by: COOP Observer
Coordinates: 37.939, -118.887 (the zone’s center; the record gives no point)

Twelve to 18 inches of snowfall fell on average west of highway 395, with the extreme high end being 25 inches at the Mammoth Ski Area. Near and east of highway 395, a general 4 to 8 inches of snow fell including 5 inches in Bridgeport and 8 inches in Lee Vining.

What these are

Winter Weather: Snow, sleet or freezing rain below warning levels that still caused disruption, damage or casualties.
Heavy Snow: Snowfall reaching the local warning threshold without the other hazards of a winter storm.

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, April 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: 226221, 226219, 226220.