A very cold air mass coupled with a strong moisture plume brought several feet of snow to higher elevations. Snow accumulated down into the foothills, impacting travel over long stretches of highways.
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 very cold air mass coupled with a strong moisture plume brought several feet of snow to higher elevations. Snow accumulated down into the foothills, impacting travel over long stretches of highways. Local flooding was reported in the Valley.
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 1, 3:01 AM PST, 2 hours 59 minutes earlier.
Area Forecast Discussion National Weather Service Sacramento CA 301 AM PST Sun Jan 1 2017 .Synopsis... Colder systems will move in today and continue into Tuesday with snow levels possibly dropping down into the foothills and northern Sac Valley. Wet but warmer pattern for mid-week into next weekend. && .Discussion... Upper level system currently dropping south through the Pacific Northwest will usher in the beginning of a wet week for NorCal. Showers will overspread the area during the afternoon and evening hours today and continue into Tuesday. Precipitation with this first wave today and Monday will be more showery and likely contained to the mountains for the most part, although a few showers possible in the Valley from time to time. Colder air will filter in which will drop snow levels as low as 500 to 1000 feet in Shasta county and to around 1000 feet for the Coastal range and western slopes of the Sierra. Going forecast largely still intact through late Monday with only slight tweaks to precipitation amounts and snow levels. Models have come in a bit warmer for Tuesday so have nudged snow levels up slightly but think cold air may be a little slow to overcome. The I-5 corridor through Shasta County could peak at 1 to 2 feet of new snow above 1000 feet through Tuesday. Could even see a dusting into the Redding area. For the eastern slopes of the Coastal Range and western slopes of the Sierra...a light dusting of snow possible around 1000 feet, but the peak snow accumulations of 6-18 inches will be above 3000 feet. Winter weather advisory remains. Model differences for later Tuesday into Wednesday lead to a lower confidence forecast for the end of the period. GFS has a brief break in the precip for most of the area Tuesday afternoon into early Wednesday while ECMWF and GEM keep the moisture flowing into the area all the way through. Regardless, additional accumulations likely with snow levels a bit higher in the 3000 to 5000 foot range. Mountain travel will continue to be impacted and additional winter weather products will probably be needed past Tuesday. Rain amounts in the valley from Sunday thru Tuesday will be light south of I-80...up to a quarter of an inch with higher amounts up to three-quarters of an inch north of I-80. Additional amounts of 0.5 to 1 inch possible on Wednesday depending on how model solutions fare in the next few days. As mentioned by previous shifts, overnight lows have trended warmer given wetter and warmer pattern...thus hard freeze potential virtually nil with valley lows in the mid 30s to low 40s. CEO && .EXTENDED DISCUSSION (Thursday THROUGH Sunday) Latest model runs have continued the trend toward wetter and milder weather for later this week, though there is still some discrepancy Thursday and Friday on how far west the closed low will retrograde off the coast. The GFS continues to indicate heavier orographic precipitation over the northern Sierra while the EC and GEM indicate more of a break in the precipitation with just some lingering showers. There's better agreement over the weekend where all the models suggest another wet system impacting NorCal. && .AVIATION... Widespread MVFR conditions with local IFR conditions developing thru the Central Valley and foothills while VFR continues across higher terrain. Another cold weather system approaches NorCal today and will bring increasing showers along with deteriorating conditions to the mountains by this afternoon while the stratus layer in the Central Valley may lift enough after 20Z for a return to marginal VFR conditions. Southerly wind gusts 15-25 kts at times in the valley, especially 20Z-06Z Monday. && .STO WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory from 10 AM this morning to 10 PM PST Tuesday for Burney Basin / Eastern Shasta County-Clear Lake/Southern Lake County-Mountains Southwestern Shasta County to Northern Lake County-Shasta Lake Area / Northern Shasta County-West Slope Northern Sierra Nevada-Western Plumas County/Lassen Park. Winter Storm Watch from late Monday night through Tuesday evening for Burney Basin / Eastern Shasta County-Shasta Lake Area / Northern Shasta County. &&
The national radar mosaic for the moment the first event began.
8 heavy snow, 3 heavy rain, 1 flood. Local standard time, as filed.
There were 12 inches of snow measured at Soda Springs by Caltrans, 24 hour total. This caused travel difficulties on Sierra highways, especially due to increased travel after the New Years holiday weekend.
There were 9.5 inches of snow measured at Kingvale at 6100 feet by a trained weather spotter, 24 hour total. Traffic on Interstate was impacted, with delays and chain controls.
There were 6 inches of snow at 2500 feet elevation 2 miles northwest of Sims. There were 2 inches on Interstate 5 at 1800 feet elevation, slowing travel.
Pacific House had 13 inches of snow at 3450 feet, Kyburz at 4058 feet had 11 inches of snow. Travel on nearby Highway 50 was slowed, with chain controls in place.
There were 6 inches of new snow, 12 inches storm total at Burney, elevation 3100 feet. This caused travel delays on Highway 299 and local roads.
There were 8 inches of new snow, 19 inches storm total at Montgomery, elevation 3800 feet. This caused travel delays on Highway 299 and local roads.
There were 30 inches of snow measured at Soda Springs/Donner Pass by Caltrans, 24 hour total. There was a storm total of 56 inches. This caused significant travel difficulties and delays on Sierra highways, with whiteout conditions at times. Numerous accidents and heavy traffic caused Caltrans to close east and west bound Interstate 80 mid afternoon through midnight. U.S. Highway 50 had traffic holds due to avalanche control.
Interstate 5 was closed 10 miles north of Redding due to snow accumulating on the road. The closure occurred between 6 pm on January 3, to 2 pm on January 4.
There was 1.73 inches of rain measured over 24 hours, 4 miles east of Kyburz.
There was 2.40 inches of rain measured over 24 hours in Pacific House, 4.56 inches storm total, over 3 days.
There were 1.99 inches of rain over 6 hours.
Minor street flooding was reported on roads near Gold Hill.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2017Every state in 2017This day in weather historyWarnings in California, January 2017
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: 674948, 674949, 674952, 674953, 674954, 674957, 674959, 677415, 674961, 674962, 674963, 674212.