An atmospheric river event beginning early December 11th brought periods of heavy rainfall, flooding from overly saturated grounds and high river/stream water levels, and heavy snow above 7000 ft. Windy conditions persisted through the event, causing trees and tree branches to fall down and localized power outages affecting hundreds of thousands of homes across Northern California. Snowfall of 1 to 2 feet caused travel problems at Sierra passes. Winds were reported to reach as high as 50-60 mph in the valley/foothill region, and over 100 mph in the mountains.
On December 22, Governor Brown declared a state of emergency for heavy rain, flooding and wind damage in counties including Tehama, Lake, Shasta, and Yolo.

Flood in TEHAMA, CALIFORNIA
From 11-DEC-14 06:00:00 to 12-DEC-14 12:00:00 (PST-8)
Location: (RBL)RED BLUFF MUNI
Flood cause: Heavy Rain
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Newspaper

Two apartment buildings suffered flooding as a creek behind the buildings over topped.  Residents were forced to evacuate.

Flood in TEHAMA, CALIFORNIA
From 11-DEC-14 12:00:00 to 12-DEC-14 10:30:00 (PST-8)
Location: DAIRYVILLE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Highway 99 was down to one lane due to flooding.

Flood in GLENN, CALIFORNIA
From 11-DEC-14 07:00:00 to 12-DEC-14 16:00:00 (PST-8)
Location: WILLOWS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Heavy rain caused closures on Highway 99W between CR 33 and 48, and portions of County Roads 33, 35, 48, Rd D just north of Willows.

Flood in GLENN, CALIFORNIA
From 11-DEC-14 06:00:00 to 12-DEC-14 15:30:00 (PST-8)
Location: KIRKWOOD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

County Roads DD, E, FF, and G had closures due to flooding.

Flood in TEHAMA, CALIFORNIA
From 11-DEC-14 06:00:00 to 11-DEC-14 15:00:00 (PST-8)
Location: TEHAMA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

There were closures numerous roads near Tehama City, between Red Bluff and Corning. These include Rawson Road-North of Gyle Road, Rawson Road-between Corona Ave and Chittenden, Rawson Road-between Dusty Way and Chard Ave,
Cone Grove Road, Christian Road, Ingraham Road, Woodland Avenue, Tehama Avenue,
Flores Avenue, Capay Road, Shasta Boulevard between 8th and 62nd, Craig Avenue
Hamilton Avenue (Gerber Area), Corning Road (Rawson Road to Black Butte), Bray Avenue, Electric Avenue, Barham Avenue at Finnell Avenue, Gyle Road from Hwy 99w through the City of Tehama, and Kauffman Avenue.

Heavy Snow in WEST SLOPE NORTHERN SIERRA NEVADA, CALIFORNIA
From 11-DEC-14 00:00:00 to 12-DEC-14 08:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

There were 19 inches of wet, heavy snow measured 3 miles ENE of Soda Springs. Heavy snow fell over 18 hours.

Heavy Snow in WEST SLOPE NORTHERN SIERRA NEVADA, CALIFORNIA
From 11-DEC-14 12:00:00 to 12-DEC-14 08:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

There were 13 inches of snow measured at the top of Kirkwood Meadows Mountain Resort, 10 inches at the base at 7200 feet.

Heavy Snow in BURNEY BASIN/EASTERN SHASTA COUNTY, CALIFORNIA
From 11-DEC-14 00:00:00 to 12-DEC-14 08:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

There were 10 inches of snowfall total measured at Baxter.

Heavy Rain in SHASTA, CALIFORNIA
From 10-DEC-14 10:00:00 to 12-DEC-14 07:00:00 (PST-8)
Location: SIMS
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

There was a storm total of 9.21 inches of rain that fell through the event, 3.68 inches fell in the last 24 hours.

Heavy Snow in MT SHASTA/WESTERN PLUMAS COUNTY, CALIFORNIA
From 10-DEC-14 16:00:00 to 12-DEC-14 07:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

There were 7 inches of snow measured at 2NW of Almanor, at 5464 feet. Heavy snow fell for 12 hours.

Strong Wind in SOUTHERN SACRAMENTO VALLEY, CALIFORNIA
From 11-DEC-14 23:00:00 to 12-DEC-14 11:00:00 (PST-8)
Magnitude: 33.00 MS
Property damage: 500.00K
Reported by: Official NWS Observations

Law enforcement, media, and the public reported numerous trees and large branches downed by winds in Sacramento and adjacent suburbs, such as Rosemont, Carmichael, and Florin. These caused local power outages spread across the area. There was a 38 mph gust measured at 7 am at Sacramento Executive Airport, a 40 mph gust at Sacramento International Airport.

Heavy Snow in MT SHASTA/WESTERN PLUMAS COUNTY, CALIFORNIA
From 10-DEC-14 16:00:00 to 12-DEC-14 07:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Snow began to stick around 1600 on 12/10/14 in the town of Twain (2800 ft elevation). There were 6 inches of snow measured at 7 am.

Flood in SAN JOAQUIN, CALIFORNIA
From 11-DEC-14 14:00:00 to 12-DEC-14 08:00:00 (PST-8)
Location: LINCOLN VLG
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Flooding was reported over numerous streets in northern Stockton.

Winter Storm in WEST SLOPE NORTHERN SIERRA NEVADA, CALIFORNIA
From 11-DEC-14 16:00:00 to 12-DEC-14 12:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

There were 14.8 inches of snow measured at Blue Canyon. Winds gusted up to 69 mph, recorded at 08:00 on December 11, 2015.

Flood in BUTTE, CALIFORNIA
From 11-DEC-14 07:00:00 to 12-DEC-14 07:00:00 (PST-8)
Location: NORD
Flood cause: Heavy Rain
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Emergency Manager

There were 5 to 11 homes with minor flooding in Nord.

Flood in BUTTE, CALIFORNIA
From 11-DEC-14 07:00:00 to 12-DEC-14 07:00:00 (PST-8)
Location: PALERMO
Flood cause: Heavy Rain
Property damage: 250.00K
Crop damage: 0.00K
Reported by: Emergency Manager

There were 25 homes with minor flooding in Palermo.

Flood in YOLO, CALIFORNIA
From 11-DEC-14 18:00:00 to 12-DEC-14 02:00:00 (PST-8)
Location: UNIV OF CAL DAVIS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Highway 113 at Covell Blvd off ramp had the right lane closed due to a washout.

Strong Wind in CARQUINEZ STRAIT AND DELTA, CALIFORNIA
From 12-DEC-14 12:00:00 to 12-DEC-14 20:00:00 (PST-8)
Magnitude: 38.00 MG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Dixon Avenue closed at Pedrick Rd. due to three power lines down over the road. Gusts to 44 mph were measured at Davis University Airport at 9:20 am.

Flood in TEHAMA, CALIFORNIA
From 11-DEC-14 06:00:00 to 12-DEC-14 12:00:00 (PST-8)
Location: VINA
Flood cause: Heavy Rain
Property damage: 300.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Multiple homes suffered flooding as Deer Creek flooded.  Residents were forced to evacuate.

High Wind in WEST SLOPE NORTHERN SIERRA NEVADA, CALIFORNIA
From 12-DEC-14 14:00:00 to 12-DEC-14 21:00:00 (PST-8)
Magnitude: 60.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Winds were 38 mph, gusting to 69 at Blue Canyon at 7:52 AM on 12/12/14.

Flood in SHASTA, CALIFORNIA
From 11-DEC-14 11:45:00 to 11-DEC-14 20:00:00 (PST-8)
Location: REDDING
Flood cause: Heavy Rain
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Boulder Creek over topped banks and flooded Premier RV Resort.

Heavy Rain in SHASTA, CALIFORNIA
From 10-DEC-14 19:30:00 to 11-DEC-14 07:30:00 (PST-8)
Location: CENTRAL VLY
Crop damage: 0.00K
Reported by: Trained Spotter

There were 3 inches of standing water in backyard, with sandbags used to protect home. Heavy rain lasted about 12 hours.

Debris Flow in LAKE, CALIFORNIA
From 11-DEC-14 08:00:00 to 11-DEC-14 12:00:00 (PST-8)
Location: CLEARLAKE OAKS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

New Long Valley Road was closed for several hours in the morning following a rock and mud slide.

Debris Flow in LAKE, CALIFORNIA
From 11-DEC-14 00:00:00 to 11-DEC-14 18:00:00 (PST-8)
Location: LAKEPORT
Flood cause: Heavy Rain
Property damage: 300.00K
Crop damage: 0.00K
Reported by: Emergency Manager

A slide at Lakeside Heights over topped the K-railing that was placed at the base of the slope and extended out into Hill Road, blocking an access to Sutter Lakeside Hospital.

Flood in LAKE, CALIFORNIA
From 11-DEC-14 12:00:00 to 12-DEC-14 00:00:00 (PST-8)
Location: LOWER LAKE PEARCE AR
Flood cause: Heavy Rain
Property damage: 400.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Flooding was reported in Clearlake, bringing significant and widespread damage. Neighborhoods were evacuated. Roads were damaged. Extensive road repair and debris removal was required.