I've never seen any proper figures to support the 'below 7 degrees' argument. I.e. a table showing temperature vs. braking distance with the same tyres on the same road surface. As mentioned though that info. is available for tread depth vs wet braking distance at 'normal' temps - more relevant as far as safety is concerned in the UK.
On a positive note, we were in Costco today and they were selling 'composite snow chains' for about £50 a pair, which looked quite handy for sticking in the boot if you are at risk of being stuck in the snow somewhere.
On a positive note, we were in Costco today and they were selling 'composite snow chains' for about £50 a pair, which looked quite handy for sticking in the boot if you are at risk of being stuck in the snow somewhere.