As soon as temperatures stay below 7 °C, winter tyres offer significantly more grip than summer tyres. In Germany there is also a situational winter tyre requirement.
Check the tread depth: 1.6 mm is the legal minimum, but at least 4 mm is recommended for good winter performance. Tyre age should not exceed six to eight years.
Check the tyre pressure regularly – it drops in the cold. Look for even wear and the alpine symbol (snowflake in a mountain).
Store summer tyres cool, dry and dark. This extends their life and keeps you safe all year round.