Tile patio and side walk where it freezes

I would like to tile my patio and side walk that are made of concrete.
Can I tile these areas in a climate that freezes?
Do I need to do anything to the thinset or grout?

I just answered this very same question in another forum.

First, you need to make sure you CAN tile this patio and sidewalk. Before we go any further, take a look at it for any cracking. Are there any cracks in the concrete? If so, get down on your hands and knees and inspect the cracks. Make sure both sides of every crack are flush. If not-- if one side is higher than the other, you might want to do something else, because there's not a membrane around that'll protect the tile from vertical movement. Also, check and make sure none of the cracks open more than 1/4" or so. If they open more than that, you may have a problem as well, as that may exceed the limitations of most membranes. If you want to check that out first, and then we'll go from there.