Winter Driving Tips

Mountain Travel in Winter Weather

Post Date:11/22/2011

Winter weather is upon us again and it is time to think about a few things before you take a drive to mountain areas.

CALTRANS has the following helpful tips that will help make your trip a safe and enjoyable one.

  • First – fill up your gas tank! 
  • Drive as conditions permit – slower acceleration, slower speeds, and slower braking in winter
    conditions. Leave extra room between you and the vehicle in front of you.
  • Use headlights, not just parking or fog lights in foggy, rainy, and snowy weather. Also remember that you must have your lights on when using your wipers.
  • If you get stuck, stay with your vehicle and wait for help.
  • If visibility diminishes to the point that you no longer feel safe driving, do not stop in the traffic
  • All vehicles, including those with four-wheel drive or snow tires should carry correctly sized chains when traveling during snowy weather. If traveling to mountain areas you should carry chains between October and April, even if it is not snowing. Weather can be unpredictable and highway signs will indicate if chains are required. If motorists do not have chains in their possession, they may not be allowed to proceed and risk being cited or fined.
  • Bring water, food, warm clothing, sturdy shoes/boots, and necessary medications.
  • Bring a charged cell phone and your cell phone charger for your vehicle. Bring a flashlight or
    battery operated radio just in case.
  • Make sure your tires are in good condition and your vehicle is running well. Check your coolant,
    brakes, windshield wipers, defroster/heater, and exhaust systems. If possible winterize your
    vehicle and have it checked by a professional mechanic before a trip to the mountains or across
    the desert.
  • If chains are required on a roadway, you may install your own chains or use the chain control
    areas or turnouts close to chain control locations – NEVER block the roadway or put chains on
    next the road or shoulder.
  • Use the Caltrans permitted chain installers at the convenient turnout locations. They will have a
    yellow bib with an official Caltrans Encroachment Permit. Do not allow non-permitted chain
    installers to put chains on your vehicle – for your safety and others.
  • Never play in the snow next to or on the roadway – it is dangerous for you, your kids, and other
    motorists. Don’t allow sleds to slide onto the road. Do not conduct snow play on private
  • Don’t have fires or barbeque along the highways or in the turnouts.
  • Always park in a safe location or turnout. Watch for “no parking” signs - you don’t want to get a
    ticket, get towed, or have an unfortunate accident.
  • Black ice can be nearly invisible so reduce your speeds during and after it snows, especially in
    turns or shady areas.
  • Make room for Caltrans equipment, CHP vehicles, and all emergency responders. Stay clear of
    snow plows!
  • What to do if you encounter fog:
    • Reduce your speed to allow for safe stopping distance
    • Drive with headlights on low beam, never drive with just parking or fog lights. 
    • Use extreme caution when crossing traffic or busy intersections. 
    • Lower your window and listen for traffic you cannot see. 
    • Use windshield wipers and the defroster to improve visibility. 
    • Be patient! Do not pass lines of traffic. 
    • If visibility diminishes to the point that you no longer feel safe driving, do not stop in the
      traffic lanes. 
    • Attempt to utilize the closest off-ramp so you can stop at a safe location and wait for the
      fog to clear.
  • Take your trash with you (including diapers) – DON’T TRASH CALIFORNIA!
  • Slow down, bring patience, and be courteous. Use turnouts if you are holding up traffic.
  • Never drink and drive…


  • R-1: Chains or snow tread tires required. Snow tires must have a tread depth of 6/32” with a “M & S” imprint on the tire’s sidewall.
  • R-2: Chains required on all vehicles except four-wheel or all-wheel drives with snow tread tires on all four wheels. Four wheel drives must carry chains. If you have four-wheel drive—engage it. Use the “4-high” range only. Use “4-low” only if your vehicle becomes stuck.
  • R-3: Chains required - ALL VEHICLES - no exceptions.


Use Caltran's "Quick Map" for road conditions, road work, chain control, cameras, and CHP information at

You may also go to or call “511” from the Inland Empire before you travel.

Follow Caltrans on twitter at


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