Question for the Northerners on my Flist

This sandal-wearing Southern gal has a question about snow. It's for a fic idea I'm toying with, so it has a purpose.

If a blizzard or Really Bad Snowstorm were to hit the Mid-West or Great Lakes Region, in say a metro area like Chicago, Detroit, Cleveland, etc., how long does it usually take for them to get major roads cleared and air travel and public transportation going again once the storm clears? A day? Two days? Doesn't have to be The Storm to End All Storms, just something beyond your average snowfall that would make national news.

Porn might result from this, so info, please! TIA.