M+S or Winter tires required in western U.S.?
I did a search of DOT websites. It appears M+S or winter (mountain-snowflake marked) tires are not required in WA, ID, MT, UT, CA, NV, AZ unless conditions warrant authorities to require them i.e....
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Second links says you must carry chains in chain areas. It even says at all times. That means year round.
Caltrans Chain guidelines
Carrying chains required in chain areas
Caltrans Chain guidelines
Carrying chains required in chain areas
