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.
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.
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.
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 10, 5:32 AM PST, 4 hours 28 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SACRAMENTO CA 532 AM PST Wed Dec 10 2014 .Synopsis... Light fog this morning with increasing clouds ahead of approaching weather system. A Strong Pacific storm impacts the area late today into Friday bringing heavy precipitation including significant mountain snow and strong damaging winds. A mainly dry weekend is expected with the next chance of precipitation early next week. && .Discussion... Plenty of clouds streaming over the north state this morning ahead of strong Pacific frontal system now poised just off the coast. Cloud cover and slightly higher wind has kept fog from becoming dense this morning so cancelled dense fog advisory for the morning. Focus turns to offshore frontal system forecast to move into northwest California this afternoon. Blended TPW image shows moisture plume associated with this system topping 1.75 inches. Strong UVV especially early Thursday will ring out this moisture bringing heavy rain and higher elevation snowfall at times. Meanwhile...tight surface and upper level gradients are predicted for strong winds. Models in fairly good agreement in shifting the main frontal band through the central valley late Thursday night or early Friday. Several warning products out at this time to account for associated incoming weather. The main adjustments to these warnings overnight included...Raising snow levels slightly in the winter storm products which should remain higher before cold air reaches the Sierra Thursday night. Separating the flood watch into northern and southern zones to account for timing of frontal movement north to south. And finally...Separating the Blizzard warning over the Sierra into northern and southern sections similar to flood warning timing and shortening the duration to account for drop off in winds by Friday morning as well as drop off in precip intensity. Most areas should see a significant drop off in winds Thursday afternoon as pressure gradients relax. Extensive cloud cover on Thursday should limit surface heating so limited instability should limit thunderstorm potential but isolated thunderstorms will remain possible. A little better thunderstorm threat exists on Friday with some partial clearing possible for a little more surface heating with California remaining under cyclonic flow through the day Friday. Upper ridging slides over the west coast Saturday for an end to the precip threat and warmer daytime highs. Night time valley fog returns Saturday morning under clearing skies. && .Extended Discussion (Sunday through Wednesday) High pressure remains over Northern California through Sunday, bringing another day of drier weather. The dry period will remain short-lived however, as another Gulf of Alaska trough moves through the region early next week. Medium-range models are in fair agreement bringing modest precipitation totals across much of the area Monday, with continued chances for showers into midweek. This should be a colder (but weaker) system than this Thursday's storm, with snow levels currently forecast to be around 4000-5000 ft. Dang && .Aviation... IFR/LIFR conditions with patchy dense fog will persist across the Valley through 18-20z today. A wet and windy storm will begin to move inland later today. This system will bring MVFR/IFR conditions beginning near KRDD-KRBL with moderate rain after 00z Thu. Winds will pick up this afternoon, and gusts up to 60-65 mph will be possible in the Valley Wednesday night through Thursday morning. Airport Weather Warnings have been issued for Redding and Stockton Airports for the winds. Dang && .STO Watches/Warnings/Advisories... high wind warning from 9 pm this evening to 2 pm pst thursday west slope northern sierra nevada...western plumas county/lassen park below 6500 feet. flood watch from this evening through friday evening burney basin / eastern shasta county...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. flood watch Thursday morning through friday evening carquinez strait and delta...motherlode...southern sacramento valley... west slope northern sierra nevada...northern san joaquin valley. blizzard warning from 7 am thursday to 4 am pst friday above 6500 feet in the west slope northern sierra nevada. high wind warning from 9 pm this evening to 2 pm pst thursday burney basin / eastern shasta county...carquinez strait and delta...central sacramento valley...clear lake/southern lake county...motherlode...mountains southwestern shasta county to northern lake county...northeast foothills/sacramento valley... northern sacramento valley...northern san joaquin valley... shasta lake area / northern shasta county...southern sacramento valley. &&
The national radar mosaic for the moment the first event began.
12 flood, 5 heavy snow, 2 heavy rain, 2 debris flow, 2 strong wind, 1 winter storm, 1 high wind. Local standard time, as filed.
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.
There were 7 inches of snow measured at 2NW of Almanor, at 5464 feet. Heavy snow fell for 12 hours.
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.
There were 3 inches of standing water in backyard, with sandbags used to protect home. Heavy rain lasted about 12 hours.
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.
There were 19 inches of wet, heavy snow measured 3 miles ENE of Soda Springs. Heavy snow fell over 18 hours.
There were 10 inches of snowfall total measured at Baxter.
Two apartment buildings suffered flooding as a creek behind the buildings over topped. Residents were forced to evacuate.
County Roads DD, E, FF, and G had closures due to flooding.
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.
Multiple homes suffered flooding as Deer Creek flooded. Residents were forced to evacuate.
There were 5 to 11 homes with minor flooding in Nord.
There were 25 homes with minor flooding in Palermo.
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.
New Long Valley Road was closed for several hours in the morning following a rock and mud slide.
Boulder Creek over topped banks and flooded Premier RV Resort.
Flooding was reported in Clearlake, bringing significant and widespread damage. Neighborhoods were evacuated. Roads were damaged. Extensive road repair and debris removal was required.
Highway 99 was down to one lane due to flooding.
There were 13 inches of snow measured at the top of Kirkwood Meadows Mountain Resort, 10 inches at the base at 7200 feet.
Flooding was reported over numerous streets in northern Stockton.
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.
Highway 113 at Covell Blvd off ramp had the right lane closed due to a washout.
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.
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.
Winds were 38 mph, gusting to 69 at Blue Canyon at 7:52 AM on 12/12/14.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2014Every state in 2014This day in weather historyWarnings in California, December 2014
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: 553868, 553869, 553870, 550022, 553856, 553865, 553867, 553860, 553863, 553864, 553917, 553858, 553859, 553862, 553855, 550021, 553857, 553861, 553866, 553871, 553872, 553906, 553915, 553914, 553918.