California, 2017Winter Weather in California, December 20, 2017
December 20, 2017 · NWS EKA · 3 events in 2 counties and zones
A cold upper trough moved south across northern California and aided in high elevation snow, as well as small hail across the coast.
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
- 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.
A cold upper trough moved south across northern California and aided in high elevation snow, as well as small hail across the coast.
Winter Weather, Northern Humboldt Interior
- When
- December 20, 7:00 AM PST
- Where
- Northern Humboldt Interior forecast zone
- Reported by
- Public
- Coordinates
- 40.705, -123.916 (the zone’s center; the record gives no point)
Snow on Wiregrass Ridge. Around 1 inch at 3000 feet, and 2 to 3 inches at 3300 feet. Location estimated. Report from social media.
Winter Weather, Southern Humboldt Interior
- When
- December 20, 8:00 AM PST to 9:00 AM PST
- Where
- Southern Humboldt Interior forecast zone
- Reported by
- Public
- Coordinates
- 40.705, -123.916 (the zone’s center; the record gives no point)
Estimated 4 inches of snow reported at an elevation of 2900 feet near Dinsmore, CA. Report taken from social media.
Winter Weather, Southern Humboldt Interior
- When
- December 20, 10:00 AM PST
- Where
- Southern Humboldt Interior forecast zone
- Reported by
- Public
- Coordinates
- 40.705, -123.916 (the zone’s center; the record gives no point)
Estimated 2 inches of snow reported at Kneeland airport. Time estimated.
- 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.
- Tornadoes in Louisiana, December 20, 2017$265,000 · EF1 · 2 events
- Tornado and Damaging Winds in Louisiana, December 20, 2017$75,000 · EF1 · 4 events
- Tornado in Texas, December 20, 2017$30,000 · EF1 · 1 event
- Tornado and Damaging Winds in Georgia, December 20, 2017$43,000 · EF0 · 4 events
- Tornado in Mississippi, December 20, 2017EF1 · 1 event
- High Wind in California, December 20, 2017$20,000 · 62 kt wind · 2 events
- Heavy Snow in North Dakota, December 20, 20179 events
- Winter Weather in Wyoming, December 20 to 21, 20179 events
- Flash Flooding and Heavy Rain in Alabama, December 20, 20177 events
- Heavy Snow in Minnesota, December 20 to 21, 20177 events
- Dust Storm and High Wind in California, December 20, 2017$10,000 · 96 kt wind · 5 events
- Flash Flooding and Heavy Rain in Hawaii, December 20 to 21, 20174 events
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 2026-09-30. Each event’s entry at NCEI: 730619, 730617, 730618.