A storm system in early January brought along widespread rain, heavy mountain snow, gusty winds, thunderstorms, and a tornado to interior Northern California on January 3rd. Chain restrictions and periods of road closures were observed by Sierra mountain passes including US Highway 50 and Interstate 80.
Every event with a place to put it. Tap one for its entry below.
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 storm system in early January brought along widespread rain, heavy mountain snow, gusty winds, thunderstorms, and a tornado to interior Northern California on January 3rd. Chain restrictions and periods of road closures were observed by Sierra mountain passes including US Highway 50 and Interstate 80. The tornado touched down briefly in a rural, unpopulated area of Tehama County and no damage or injuries occurred, and was rated an EF-U.
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 Jan 3, 3:02 AM PST, 3 hours 58 minutes earlier.
Area Forecast Discussion National Weather Service Sacramento CA 302 AM PST Fri Jan 3 2025 .SYNOPSIS... A weather system today brings widespread precipitation, moderate to heavy mountain snow, gusty southerly winds, and isolated thunderstorms throughout the day. Dry and warming weather will follow over the weekend and into next week with periods of gusty north to east winds. && .DISCUSSION... RADAR at 1:30am this morning is already showing showers over the Coastal Range and northern Sacramento Valley, which are associated with a quick moving weather system that will be moving inland throughout the day today. As the trough moves inland, we can expect widespread precipitation, moderate to heavy mountain snow, gusty southerly winds, and isolated Valley and foothills thunderstorms. Generally we're expecting around 0.5 to 1 inch of rain in the northern Sacramento Valley today, 1 to 2 inches in the foothills and mountains below snow level, and 0.1 to 0.5 inches in the remainder of the Sacramento Valley, northern San Joaquin Valley, and Delta region. The NBM also still shows a 10 to 20% probability of isolated thunderstorms in the Valley and foothills between 10am and 8pm. Any storms that pop up would impact local rain totals, though rain rates still look to remain below debris flow thresholds for burn scars. Snow amounts have once again trended just a bit higher with the latest forecast, though impacts will remain largely the same despite this slight increase. Our Winter Storm Warning remains in effect from 7am to 10pm PST today, for elevations above 5500 ft in the northern Sierra Nevada and southern Cascades. The NBM has a 35 to 70% chance of 8 inches or more over 24 hours, with snow levels starting around 5500 to 6500 ft when snow begins and lowering to 4500 to 5500 ft in the afternoon. Travel delays, chain controls, road closures, and significant reductions in visibility remain possible throughout the storm today. Be sure to stay up to date with the latest weather forecast at weather.gov/sto and road conditions at quickmap.dot.ca.gov! On Saturday, a few mountains shower and snow showers may remain in the morning, but barring this, drier weather is expected to return to the region over the weekend. Upper level ridging will build back into the region over the weekend, bringing drier and slightly warmer weather that continues into the extended forecast period. && .EXTENDED DISCUSSION (Tuesday THROUGH Friday)... Inside slider short wave trough progged to drops south through interior NorCal Tuesday. Dry weather expected except for a slight chance of light snow showers over higher elevations of the Sierra Nevada. Main impact will be breezy to windy north to east wind Tuesday. Gusty wind continues Wednesday as EPAC upper ridging builds inland. Areas of gusty north to east wind continue in the northern and eastern foothills/mountains through the remainder of the week. Above normal high temperatures expected through the extended period with mainly 60s in the Central Valley and 40s to lower 60s for the mountains and foothills. && .AVIATION... In Sac Vly/Delta, widespread MVFR with lcl IFR til 01z Sat in precip, then lcl MVFR cigs/vsby til 17z Sat. Isold tstms possible btwn 20z-03z. Areas of Sly sfc wind 15-20 kts possible btwn 15z-00z. In N San Joaquin Vly, lcl MVFR vsby in BR possible til 16z. Lcl MVFR cigs btwn 18z-01z, then areas MVFR/IFR in BR aft 06z Sat. Sfc wind mainly below 12 kts next 24 hrs. In foothills/mtns, widespread MVFR/IFR aft 17z with lcl LIFR obscurring trrn. Isold tstms possible, mainly N of I-80, btwn 20z-04z. Snow levels AOA 5000 ft thru 00z Sat, lowering to 3000-4000 ft overnight. Areas SWly sfc wind gusts 30-45 kts over mtns til 06z Sat. && .STO WATCHES/WARNINGS/ADVISORIES... Winter Storm Warning from 7 AM this morning to 10 PM PST this evening for West Slope Northern Sierra Nevada-Western Plumas County/Lassen Park. &&
The Beale AFB radar (KBBX), 97 km away, was scanning. The volume nearest the first event began at 21:37 UTC.
2 heavy snow, 1 flood, 1 tornado. Local standard time, as filed.
A CoCoRaHS observer measured 0.4 inches of snow in Shingletown on January 3rd at 3,964 feet. The National Operational Hydrologic Remote Sensing Center estimated 6 to 12 inches of snow above 5500 feet, with up to 18 inches at Lassen Peak.
On January 3rd, Caltrans District 3 measured 10 inches of snow at Kingvale, Castle Peak, and Soda Springs. Sierra ski resorts measured 5 to 13 inches of snow. UC Berkeley Central Sierra Snow lab measured 12.8 inches of snow. 5 to 14 inches of snow were estimated from automatic CDEC sensors. The National Operational Hydrologic Remote Sensing Center estimated snow amounts of 6 to 18 inches. Traffic was held in the Sierra on Interstate 80 and US Highway 50 for a total of 5 hours and 1 hour respectively due to multiple spinouts from winter weather conditions. Periods of chain restrictions were in place through the day.
California Highway Patrol reported impassable conditions due to flooding and rocks in the roadway on Inskip Road and Lanes Valley Road.
Between approximately 5:18 pm and 5:21 pm local time on Friday a trained spotter and area webcam footage showed a brief tornado about 8 miles northeast of Dairyville in an unpopulated area of Tehama County. There were no damage or injury reports. The determination is that this was an EF-U (unknown) tornado that touched down for approximately 3 minutes with a path length of approximately 0.8 miles and unknown peak wind.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2025Every state in 2025This day in weather historyThe tornado archive for California, 2025Warnings in California, January 2025
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: 1226546, 1226547, 1226544, 1226545.