I've seen quite a bit of 911 used in winter. Especially with the four wheel drive, it is apparently an amazing winter vehicle. It has also gone through extensive winter testing from Porsche prior to launch. I think in the 2007 CarandDriver magazine, they could not stop commending how well the 997.1T performed in winter.
Also, Calgary winters are normal just cold. Living there for 6 years, there has been very low amount of snow accumulation compared to other cities (Toronto), if I'm not mistaken, we rarely see more than 15cm of snow at a time. Obviously, there were a couple of days were the snow was 30+cm but to be honest, in Calgary it is very rare.
M3.e90 JZB blacked out.coded