Well, it's been working fine for me for about 15 years, let's agree to disagree here. I would still find it easier to remember to change the tires at +1°C than whatever the hell it comes down to in Fahrenheit.
I too live in a region with 80 (Celsius) degree yearly variation (sometimes more; the maximum yearly difference I've lived through is about 90 degrees IIRC: -45 in January to +43 in July), and Fahrenheit makes absolutely no sense to me in this climate.
> Well, it's been working fine for me for about 15 years, let's agree to disagree here.
If you want to convince yourself, go out on the road in non-winter tires when it is sub-40F, find an open space where you can experiment, and then do a panic stop. Like you might have to do if someone jumps out in front of you.
That is what convinced me to not wait until it was freezing before I put on cold weather tires.
Winter tyres are less to do with freezing water and more to do with the way the tire compound in summer tires hardens/loses elasticity and therefore grip in lower temperatures, around 7 degrees Celsius.
I too live in a region with 80 (Celsius) degree yearly variation (sometimes more; the maximum yearly difference I've lived through is about 90 degrees IIRC: -45 in January to +43 in July), and Fahrenheit makes absolutely no sense to me in this climate.