Driving to Colorado This Winter? This New Tire Law Could Ruin Your Ski Trip

Colorado just turned its traction law into a personality test for skiers: are you the guy who checks tires in the rental lot, or the guy sideways on Vail Pass with a state trooper writing you up? As of this fall, the updated law requires at least 3/16-inch tread and proper winter, all-weather, or M+S tires on key stretches of I-70 when the law is active, according to Colorado DOT’s traction-law page. If your setup doesn’t qualify, you need chains or an approved traction device—no matter how many AWD badges are on your tailgate.