Originally Posted by TransitBiker

Well, there's snow then there's ice. If it's icy out the only real option is to ride in the middle of the lane so no one tries to pass you, reducing the risk of being hit. You also need to have proper tires for riding in icy conditions. Slicks are no good, you need at least a somewhat raised tread to have gripping edges. If the road is cleared, you gotta be wary of those weird lil parts where the shoulder vanishes under a mound of icy snow, or parts where the plow trucks missed & get compacted down. It can be tricky, but proper tires will usually track reliably over all of this..

- Andy