It isn't the snow you need to worrry about, as much as it is the lower temperatures that will make your all season tires go hard and slippery. Five months of the year in Colorado Springs you could have winter tires on, given average monthly temperatures.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue