A late spring storm brought snow and travel impacts to the mountains of interior Northern California on April 24th - 26th.
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.
The episode as NWS STO wrote it up.
A late spring storm brought snow and travel impacts to the mountains of interior Northern California on April 24th - 26th.
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 Sacramento, CA wrote its last area forecast discussion before the first event at Apr 24, 2:04 AM PST, 7 hours 56 minutes earlier.
Area Forecast Discussion National Weather Service Sacramento CA 304 AM PDT Sat Apr 24 2021 .SYNOPSIS... Light scattered showers mainly north of I-80 through this afternoon. A winter storm will bring widespread rain and impactful mountain snow tonight through Sunday with mountain showers lingering into Monday. Significant mountain travel impacts expected. Thunderstorms possible Sunday afternoon and evening. Warm and dry weather returning Tuesday through next week. && .DISCUSSION... The initial upper trough has begun to move across Northern California this evening. Radar shows light reflectivity across much of the CWA, although low level dry air is hindering much precipitation making it to the ground. Main area for light QPF through the morning will be in Shasta County, and the foothills/mountains north of I-80, although some Valley showers in the northern portion of the forecast area cannot be ruled out. Snow levels remain above 5500 feet through the overnight hours, increasing again with daytime warming. Primarily dry weather this afternoon although some additional isolated to scattered showers will be possible north of I-80. Onshore flow is bringing some gusts from 20-30 mph to interior NorCal this morning, with breezy winds expected to continue today. Main trough axis approaches California late tonight with impacts from this weather system continuing through Monday. Precipitation will spread from north to south during the overnight hours, becoming widespread by Sunday morning and afternoon. The forecast appears to be on track for snow and rain amounts with only minor changes made in the overnight package. The Winter Storm Warning continues for above 4500 feet beginning tonight and continuing through Monday morning. Minor snow accumulations will be possible down to 3500-4000 feet both Sunday and Monday mornings. The heaviest mountain snow and Valley precipitation are expected on Sunday. Along with the wet weather, gusty onshore are expected again tomorrow which may lead to reduced visibilities especially in the mountains with falling snow. Mountain travel delays and chain controls are expected Sunday. Thunderstorms will be possible Sunday afternoon and evening across the CWA, although they will greatly depend on how much instability can be reached as cloudy skies are anticipated much of the day. The best chances remain in the western portion of the Sacramento and northern San Joaquin valleys, although some foothill/mountain storms cannot be ruled out. Hodographs indicate favorable conditions for rotating storms if they do manifest, and funnel clouds or a brief tornado would be possible. The other threats with any storm would be small accumulating hail, gusty winds, and periods of heavy rain. Keep an eye on the forecast as details about storm potential become more clear. Precipitation becomes much more showery early Monday morning with lingering mountain travel impacts possible as light precipitation continues through the day. The trough finally moves east of the area Monday night with ridging building in on Tuesday. Cool weekend and Monday temperatures warm back up to near average by Tuesday afternoon. && .EXTENDED DISCUSSION (Wednesday THROUGH Saturday)... Warm and dry weather expected later next week as strong high pressure covers the region. Highs will warm to around 10-15 degrees above average by Thursday and Friday with mid 80s to lower 90s possible across the Central Valley. Ensembles indicate slight weakening of the ridge next weekend as a series of short- waves pass to our north through the PacNW potentially leading to slight cooling. && .AVIATION... VFR conditions predominate the next 24 hours. Scattered light precipitation (snow above 055-065) will be possible north of I-80 with local MVFR conditions at times. Widespread southerly surface wind gusts 15-30 kts. && .STO WATCHES/WARNINGS/ADVISORIES... Winter Storm Warning from 11 PM this evening to 11 AM PDT Monday for West Slope Northern Sierra Nevada-Western Plumas County/Lassen Park. &&
4 winter storm. Local standard time, as filed.
Trained spotters in Chester and Quincy reported 7 and 2.25 inches of new snow accumulation respectively. Elevations for each station are 4500 feet and 3750 feet respectively.
A CoCoRaHS observer 5.3 miles east north-east of Shingletown reported 1.5 inches of new snow.
Caltrans reported 2 and 4 inches of new snow accumulation at their Soda Springs and Kingvale maintenance yards.
Alpine Meadows/Squaw Valley and Kirkwood reported 6 and 4 inches of snow respectively. Elevation for these reports are 7880 and 7690 feet respectively.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2021Every state in 2021This day in weather historyWarnings in California, April 2021
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 2026-09-24. Each event’s entry at NCEI: 955166, 955167, 955168, 955169.