MARYSVILLE – Caltrans District 3 is alerting motorists to prepare for snowy driving conditions in the Sierra Nevada region and watch for flash floods in areas impacted by the Camp Fire Wednesday through Friday.

The National Weather Service (NWS) has issued a Holiday Storm Warning for a weather system expected to arrive Wednesday afternoon and continue through Friday morning. Periods of heavy rainfall are expected in Northern California turning to snow above 5,500 feet as the storm system moves into the Sierra Nevada. Snowfall for Donner Summit is predicted to be 8 to 12 inches with lower levels of snow in South Lake Tahoe Wednesday and Thursday. Snow levels are expected to rise to 7,000 feet Friday, impacting Donner Summit traffic.

This storm, in addition to increased traffic for the Thanksgiving holiday, will result in traffic delays for motorists. Those traveling through the Sierra region Wednesday afternoon and evening should account for significantly increased travel time.

Chain controls on Interstate 80 over Donner Summit, on U.S. Highway 50 over Echo Summit and on other Sierra mountain roadways should be anticipated Wednesday afternoon through Friday morning. Caltrans permitted and trained chain installers on Interstate 80 can be identified by a reflective sign with their bib number.

Moderate to heavy rain is forecasted beginning Wednesday afternoon and will continue into Friday morning. Motorists should be alert for potential flash floods in Butte and Plumas counties caused by ash or debris flow in new burn scar areas caused by the Camp Fire.

In preparation for the rain in impacted Camp Fire areas, Caltrans has been working with cooperating local and state agencies to protect infrastructure and mitigate for post-fire floods and debris flow. Highway maintenance crews have been cleaning and checking culverts, installing straw wattles, and performing hydroseeding and erosion control operations along State Routes 191 and 70.

Severe weather may slow motorists, resulting in roadway congestion. Wet and slippery roadways reduce tire traction, especially at high vehicle speeds. Hydroplaning caused by vehicle speed and rain accumulations on the roadway can result in loss of driver control. Motorists are encouraged to slow down and observe the following winter driving tips, which can also be found at


  • Check your tire pressure and tread depth to minimize sliding and/or hydroplaning.
  • Replace the wiper blades and fill the windshield wiper fluid reservoir; be sure to use a winter formula to help de-ice windshields.
  • If traveling to higher elevations, carry tire chains that are the correct size for your tires, and practice installing the chains before needing to use them.
  • Have a full tank of fuel before traveling.


  • Have blankets, extra clothing, food and water, towels, a shovel, a flashlight, an ice scraper, a small bag of sand or kitty litter and road flares.
  • Have a fully charged cell phone before leaving and carry a car charger.


  • Reduce speeds during winter weather and allow for additional stopping time.
  • Turn on headlights to see and be seen and turn off cruise control.
  • Watch for snow removal equipment. Only pass snow removal vehicles when a safe, legal passing area is available and sight distance is good.
  • Use extra caution on bridges, ramps, and shaded areas; they may freeze first.
  • If your vehicle begins to skid, steer in the direction of the slide and slowly remove your foot from the accelerator.


  • Check out Caltrans’ “QuickMap” for current road conditions and chain requirements at A mobile version is also available.
  • Motorists also can use the California Highway Information Network automated phone service by calling 1-800-427-ROAD (7623).
  • Motorists can see real-time conditions before they hit the road by using our map of traffic cameras in the Sacramento Valley, up Interstate 80, U.S. Highway 50 and around the Tahoe Basin.
  • Follow Caltrans District 3 on Twitter @CaltransDist3 and Facebook to receive the latest information about current roadway conditions.
  • For forecast information, visit the National Weather Service website.


  • Understand that winter weather and road conditions can change rapidly and allow for extra travel time.
  • Make sure you share the route you intend to take with friends or family.
  • Exercise patience and respect for other motorists.

Caltrans crews will be working around the clock to keep the roadways open and clear. Motorists are urged to be “Be Work Zone Alert” and to “Slow for the Cone Zone.”