Winter Weather in California, December 27 to 28, 2020

Name: Winter Weather in California, December 27 to 28, 2020
Start: 2020-12-27T07:00
End: 2020-12-28T07:00
Location: California

December 27 to 28, 2020 · NWS REV · 2 events in 2 counties and zones

A quick-moving closed upper low brought light to moderate snow to the northern and central Sierra from the 27th into the 28th. This lead to slick roads in the Sierra for the Monday morning commute.

Where it happened

Every event with a place to put it; 2 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: 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 REV wrote it up.

A quick-moving closed upper low brought light to moderate snow to the northern and central Sierra from the 27th into the 28th. This lead to slick roads in the Sierra for the Monday morning commute.

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 Reno, NV wrote its last area forecast discussion before the first event at Dec 27, 2:24 AM PST, 4 hours 36 minutes earlier.

Area forecast discussion, Dec 27, 2:24 AM PST, 4 hours 36 minutes before

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In the hours before

Special weather statement, Dec 27, 2:43 AM PST, 4 hours 17 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 winter weather. Local standard time, as filed.

Winter Weather, Greater Lake Tahoe Area

When: December 27, 7:00 AM PST to December 28, 7:00 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)

Less than 1 inch of snow fell near and west of California Highway 89 with up to 1 inch falling along the Sierra crest northwest of Lake Tahoe. Near Truckee, snowfall amounts were less than a half-inch. South of US Highway 50, 3 inches of snow fell at Heavenly Ski Resort.

Winter Weather, Mono

When: December 27, 7:00 AM PST to December 28, 7:00 AM PST
Where: Mono forecast zone
Reported by: Public
Coordinates: 37.939, -118.887 (the zone’s center; the record gives no point)

A dusting of snow fell near Bridgeport, with 6 to 12 inches of snow accumulating along the central Sierra crest at June Mountain and Mammoth Mountain Ski areas. Near Toms Place, 2 to 6 inches fell west of US Highway 395.

What these are

Winter Weather: Snow, sleet or freezing rain below warning levels that still caused disruption, damage or casualties.

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

The same day elsewhere

Every storm in California in 2020 Every state in 2020 This day in weather history Warnings in California, December 2020

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: 944516, 944518.