Winter is still more than a month away, but Colorado's winter driving season has arrived and here's what  you need to know about the state's chain law for passenger vehicles.

We are all used to seeing the CDOT signs signifying chain restrictions over mountain passes, and we are all used to ignoring the signs, knowing that it applied only to commercial vehicles. But, how we travel the I-70 corridor is changing.

Colorado motorists need to be aware of the Traction Law, and the Passenger Vehicle Chain Law.

Whenever a Traction Law is implemented(Code 15), all motorists must have snow tires, tires with the mud/snow designation, a four-wheel drive vehicle, or tires with a minimum 1/8 inch tread.

To test your tread, take a quarter and insert it into the tire tread with the head down. If the top of George Washington's head is covered by tread,  you are good to go. If not,. you can't drive during the Traction Law - and you probably need new tires.

During severe winter storms, CDOT can enact the Passenger Vehicle Chain Law(Code 16) - which is the final measure take before a highway is closed. Under this law, all vehicles on the road must have chains or an alternative traction device.

Fine for having inadequate equipment  could be at least $130, and if you are in an accident and/or block the roadway because of inadequate equipment it could be more than $650.

The smartest, safest, and least expensive course of action is to make sure that you have adequate tires before hitting the highway.