Driving on studded snow tires will become illegal for the season after April 30 in Idaho, and the Idaho Transportation Department is reminding people that violations carry a $67 fine. They’re also advising against driving on studded tires when roadways are bare to avoid severe damage to roads; Idaho’s unseasonably warm winter prompted many of us to remove those winter tires months ago. Studded tires already are illegal in Utah, Oregon and Washington for the year, as their deadline was March 31. Nevada allows them through April 30; Montana through May 31; and Wyoming all year.