When you change between summer and winter tyres, it is an obvious time to check the tyres. Suppose you let a service station do the change for you. They will be able to give an expert opinion on the condition of your summer tyres as they take them off and then make sure that your winter tyres are in good condition before putting them on. If the summer tyres don´t have sufficient tread for another season, you might want to consider purchasing a new set already now and store the rims with new tyres on them. That will save you stress when the winter is over, as you don´t have to start looking for new tyres when you just want to start enjoying the spring weather. For more information regarding tread depth, visit: https://blogagoraoununca.com/how-often-should-you-check-your-tread-depth/