By this point, as we enter the middle of May, most drivers who use soft-compound winter tires have likely switched them out for a set of all-season rubber, or even some higher-performance summer-only tires.
However, what happens if you keep those winter tires on your car and run them in warm temperatures?
Jason Fenske of Engineering Explained is here with the answer, backed by hard data as always. Long story short: it's not a good idea.
Winter tires are made of a much softer compound and are designed with multiple sipings (or thin slits) in the tread blocks. This all gives tire better traction in all sorts of variable winter conditions and provides grip in cold temperatures.
When faced with dry, warm pavement, it's a different story. After three brake tests, Jason's set of Bridgestone Blizzaks showed considerable wear and loss of grip, fading from a 0-60 mph stopping distance of 127.72 feet in the first test to 134.9 feet in the third.
Then Jason did the exact same test with a set of Yokohoma Geolander G95 all-season tires. Stopping distances remained consistent at 123.72 feet in the first test and 126.76 feet in the third. The tests were performed with identical variables, including new tires and a 63-degree Fahrenheit temperature.
So, why won't the softer compound hold grip in warm weather? Jason says it's because the soft compound is literally tearing away from the tire and being destroyed as the brakes are applied. Thus, they lose their shape and don't slow the vehicle down appropriately.
The all-season tires are firmer and hold their shape better. The movement in the winter tires' tread blocks also make for more movement in the tire and don't provide better grip.
There you have it. With this new knowledge, make sure to install all-season tires before your set of winter rubber takes a beating this spring and summer. (And don't skimp out on high-quality tires in general.)