Winter Weather and Heavy Rain in California, April 4 to 6, 2020

Name: Winter Weather and Heavy Rain in California, April 4 to 6, 2020
Start: 2020-04-04T05:00
End: 2020-04-06T08:00
Location: California

April 4 to 6, 2020 · NWS EKA · 8 events in 4 counties and zones

A late season winter storm moved across northwest California during early April. Accumulating snowfall was observed across the interior mountains, while small hail was observed near the coast.

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: 8

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 EKA wrote it up.

A late season winter storm moved across northwest California during early April. Accumulating snowfall was observed across the interior mountains, while small hail was observed near the coast.

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 Eureka, CA wrote its last area forecast discussion before the first event at Apr 4, 3:27 AM PST, 1 hour 33 minutes earlier.

Area forecast discussion, Apr 4, 3:27 AM PST, 1 hour 33 minutes before

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Hazardous weather outlook, Apr 4, 3:53 AM PST, 1 hour 7 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

7 winter weather, 1 heavy rain. Local standard time, as filed.

Winter Weather, Northern Trinity

When: April 4, 5:00 AM PST to 11:50 AM PST
Where: Northern Trinity forecast zone
Reported by: Trained Spotter

One inch of snow measured by a trained spotter. The approximate elevation of the report was 2600 feet.

Winter Weather, Northern Trinity

When: April 4, 5:00 AM PST to 12:30 PM PST
Where: Northern Trinity forecast zone
Reported by: Public

Eight-tenths of an inch of snow occurred at an elevation of 2300 feet.

Winter Weather, Southern Trinity

When: April 4, 5:00 AM PST to 2:12 PM PST
Where: Southern Trinity forecast zone
Reported by: Public
Coordinates: 40.651, -123.113 (the zone’s center; the record gives no point)

Three inches of snow occurred at an elevation of 2200 feet.

Winter Weather, Northern Trinity

When: April 4, 5:00 AM PST to 1:10 PM PST
Where: Northern Trinity forecast zone
Reported by: Public

Two inches of snow at an elevation of 2800 feet.

Heavy Rain, Humboldt

When: April 4, 5:00 AM PST to 4:49 PM PST
Where: Humboldt County, 1.08 mi SSW of Richardson Grove
Reported by: Law Enforcement
Coordinates: 40.005, -123.788

California Highway Patrol reported small rock slides occurring across Highway 101 due to flowing water.

Winter Weather, Northern Trinity

When: April 4, 5:00 AM PST to 11:25 PM PST
Where: Northern Trinity forecast zone
Reported by: Trained Spotter

Two inches of snow at an elevation of 2500 feet.

Winter Weather, Northwestern Mendocino Interior

When: April 4, 5:00 AM PST to April 6, 12:00 AM PST
Where: Northwestern Mendocino Interior forecast zone
Reported by: Trained Spotter
Coordinates: 39.434, -123.432 (the zone’s center; the record gives no point)

Trained spotter reported 3 inches of storm total snowfall at an elevation of 3805 feet.

Winter Weather, Northern Trinity

When: April 4, 5:00 AM PST to April 6, 8:00 AM PST
Where: Northern Trinity forecast zone
Reported by: COOP Observer

Five inches of storm total snow. The approximate elevation of the report is 2600 feet.

What these are

Winter Weather: Snow, sleet or freezing rain below warning levels that still caused disruption, damage or casualties.
Heavy Rain: Rainfall totals unusual for the place and season that did not produce a flood.

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, April 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: 884852, 884854, 884856, 884859, 884863, 884865, 884867, 884872.