A potent winter storm brought mountain snow, valley rain, and gusty winds to interior northern California from December 6 through the 8th. One to two feet of snow fell for elevations above 5500 feet, bringing difficult driving conditions and chain controls to most of the mountain passes.
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 potent winter storm brought mountain snow, valley rain, and gusty winds to interior northern California from December 6 through the 8th. One to two feet of snow fell for elevations above 5500 feet, bringing difficult driving conditions and chain controls to most of the mountain passes. Down in the Valley and foothills, one to four inches of rain fell which brought slick road conditions and minor roadway flooding. Finally, gusty winds around 30-40 mph resulted in downed trees and some power outages.
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 Dec 6, 2:30 PM PST, 30 minutes earlier.
Area Forecast Discussion National Weather Service Sacramento CA 230 PM PST Fri Dec 6 2019 .SYNOPSIS... A strong winter storm will bring periods of heavy rain, mountain snow, strong winds and hazardous travel Friday and into the weekend. Dry conditions return next week with near average temperatures. && .DISCUSSION... A deep closed low progressing towards northern California will bring periods of rain, snow, and strong winds to the area. Early this afternoon, rain has already moved into the northern and coastal mountain and foothill areas of Shasta and Tehama Counties and will continue to progress southeast ward through the evening. Hi-res guidance suggests precipitation spreading into the Sacramento area between 5-7 pm, reaching the majority of the Sierra Nevada shortly after. HREF probabilities suggest the potential for over a half inch of rain an hour for portions of the foothill and Valley regions as this initial band of precipitation moves in , including some of the 2018 burn scars tonight (mainly the Carr/Hirz/Delta and Mendocino Complex burn areas). Rain continues through the overnight hours with model (ARW/NAM) continuing to indicate the potential for a band of intense rainfall setting up across Lake Co to Chico to Susanville early tomorrow morning, and continuing to move southeast before moving south of the area. Scattered showers continue across the Valley and foothill regions Saturday, along with the potential for some thunderstorms mainly during the late morning and afternoon hours. The mid-level cyclone will be spreading inland across northern California Saturday bringing mid level cooling and unstable conditions leading to scattered thunderstorm across the Valley into the foothills with additional concerns for heavy rain over the burn scars (including the Camp burn area). A Flash Flood Watch has been issued for all three burn scars mentioned from this evening through tomorrow evening due to the potential for heavy rain and thunderstorms. Total precipitation amounts in the Valley for this system range anywhere from a half inch in the southern Sacramento Valley, up to two and a half towards the north. Heavy mountain snow will begin tonight in the Sierra Nevada, mainly at elevations above 6500 feet. Significant travel impacts are expected to begin this evening, continuing most of the weekend as snow continues to fall. Gusty winds may create near white out conditions at times in combination with heavy snowfall rates. Snow levels do drop slightly by early Sunday morning as the low moves over NorCal, with snow down to about 5500 feet. Feet of snow are still expected by the end of this system. The Winter Storm Warning begins this evening and extends through the early afternoon Sunday. In addition to the precipitation, tightening pressure gradients will lead to southerly gusty winds across a majority of the Sacramento Valley as this system moves onshore. Sustained winds around 20 to 30 mph will be seen overnight and into early tomorrow afternoon, with gusts ranging from 30 to 50 mph. The strongest winds look to be in the northern Sacramento Valley. A Wind Advisory has been issued for this time when the strongest winds are expected. Winds will remain breezy through early Sunday, before becoming light again Sunday night. Some lingering showers will be possible Sunday afternoon, with conditions expected to clear later Sunday night as the mid level wave pushes out of NorCal. Ridging returns Monday with average temperatures and dry weather expected. && .EXTENDED DISCUSSION (Tuesday THROUGH Friday)... Dry weather continues for interior NorCal Tuesday as upper level ridging remains in place. Ensemble guidance continues to bring a weak trough through California Wednesday. Both GFS and Euro ensemble and deterministic guidance still suggesting a slight chance of light showers over the Coastal mountains and southern Cascades late Tuesday into Wednesday, though afternoon NBM significantly backed off on precip chances. Therefore, blended slightly down so chances are now mainly overnight Tuesday. Zonal flow takes over Thursday into the weekend after the trough moves through. Guidance shows slight chance of precip over northern Shasta county Thursday and Friday as weak impulses move along the flow. HEC && .AVIATION... Widespread precipitation next 24 hours with MVFR conditions, locally IFR/LIFR in heavier showers. Southerly wind gusts up to 30-45 kts are expected in the Valley decreasing after 00z-03z Sunday; gusts up to 40-55 kts mountains. Snow levels 6500 feet tonight, then 5500-6000 feet Sunday. && .STO WATCHES/WARNINGS/ADVISORIES... Winter Storm Warning until 1 PM PST Sunday for West Slope Northern Sierra Nevada-Western Plumas County/Lassen Park. Flash Flood Watch from 7 PM PST this evening through Saturday afternoon for Central Sacramento Valley-Clear Lake/Southern Lake County-Mountains Southwestern Shasta County to Northern Lake County-Northeast Foothills/Sacramento Valley-Northern Sacramento Valley-Shasta Lake Area / Northern Shasta County-Western Plumas County/Lassen Park. Wind Advisory from 10 PM this evening to 1 PM PST Saturday for Carquinez Strait and Delta-Central Sacramento Valley-Mountains Southwestern Shasta County to Northern Lake County-Northeast Foothills/Sacramento Valley-Northern Sacramento Valley-Northern San Joaquin Valley-Southern Sacramento Valley. &&
The national radar mosaic for the moment the first event began.
11 winter weather, 4 heavy rain, 3 flood. Local standard time, as filed.
A trained spotter reported that 5.75 inches of rain had fallen over 24 hours. The 2 day total was 6.68 inches.
A trained spotter reported a total of 1.4 inches of rain had fallen at 1600 hours on December 7.
A trained spotter reported 2.05 inches of rain fell over 12 hours.
Kirkwood Mountain Ski Resort reported 5 inches of new snow over a 24 hour period on December 7. On December 8, the ski resort reported an additional 12 inches of snow, putting the storm total to 17 inches. The elevation of the snow report is 7690 feet.
Bear Valley Ski Resort reported 3 inches of new snow over a 24 hour period on December 7. On December 8, the ski resort reported an additional 9 inches of snow, putting the storm total to 17 inches. The elevation of the snow report is 7690 feet.The elevation of the snow report is 8500 feet.
Caltrans reported 2 inches of new snow over a 24 hour period on December 7 in Bear Valley. On December 8, they reported an additional 4 inches of snow, putting the storm total to 6 inches. The elevation of the snow report is 7200 feet.
Caltrans reports 24 hour snow report of 1 inch at Cabbage Patch maintenance yard, elevation 6800 feet.
Sierra-at-Tahoe Ski Resort reported 5 inches of new snow over a 24 hour period on December 7. On December 8, the ski resort reported an additional 14 inches of snow, putting the storm total to 19 inches. The elevation of the snow report is 8852 feet.
Caltrans reported 2 inches of new snow over a 24 hour period on December 7. On December 8, they reported an additional 5 inches of snow, putting the storm total to 10 inches. The elevation of the snow report is 6100 feet.
Caltrans reported 7 inches of new snow over a 24 hour period on December 7. On December 8, they reported an additional 15 inches of snow, putting the storm total to 22 inches. The elevation of the snow report is 6800 feet.
Soda Springs Ski Resort reported 12 inches of new snow over a 24 hour period on December 8. The elevation of the snow report is 7300 feet.
Sugar Bowl Ski Resort reported 6 inches of new snow over a 24 hour period on December 7. On December 8, the ski resort reported an additional 17 inches of snow, putting the storm total to 24 inches. The elevation of the snow report is 8383 feet.
Dodge Ridge Ski Resort, in Tuolumne County, reported 7 inches of new snow over a 24 hour period on December 8. The elevation of the snow report is 8200 feet.
Boreal Ski Resort reported 12 inches of new snow over a 24 hour period on December 8. The elevation of the snow report is 7700 feet.
A trained spotter reported widespread street flooding due to heavy rain. Spotter noted 0.61 inches of rain had fallen.
Caltrans reports highway 273 is blocked in both directions at Ellis St due to flooding. 0.72 inches of rain reported at Redding Airport in the last hour. Ending time is based on radar data.
California Highway Patrol reports roadway flooding at highway 44 and Airport Rd and that Caltrans is closing the off ramp due to flooding. Flooding end time is based off radar analysis.
California Highway Patrol reports roadway flooding at Interstate 5 on the North Street off ramp. Flooding end time is based off radar analysis.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2019Every state in 2019This day in weather historyWarnings in California, December 2019
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: 869250, 869248, 869251, 869237, 869238, 869239, 869240, 869241, 869242, 869243, 869244, 869245, 869246, 869247, 869249, 869252, 869253, 869254.