Okay, so we didn't get a blizzard this time, but hey, this is Chicago. You know we're going to get a big snow storm this year. It's just a matter of when.
Preparing for a blizzard is the same as preparing for any potential disaster -- be informed, have a plan, make a kit. But for blizzards, you need a few special things:
In the car: something to dig out the car and get it unstuck; something for warmth; something for light; something to eat and drink. And don't hit the road with less than half a tank of gas. If you're stuck on the highway for hours (days?), half a tank is not going to cut it.
At home: What if you couldn't get to the grocery store for three days? What if the power and the heat go out? Make sure you have enough food and drink that don't require cooking, and some way to safely heat up a room. And don't forget to get some movies and books to pass the time.