20degF is a big plus. too cold for ice, generally, and the snow will have good grip. The worst conditions are right around freezing - 30-32deg when you can get ice and slush and then ice in pockets of shade. Temps in the low 20's helps a lot. You will be just fine. Just remember to brake early and gently - takes longer to stop in the snow. Also going down hills it is better to shift into a lower gear manually so you use less brakes.

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2003 4.6is - SOLD
2003 M5 Imola
2008 Mini Cooper S
2011 Mazda CX9