Winter Bike recommendation request
I live in Worcester, MA and work in Westford. I ride my Specialized Roubaix about an hour everyday during my lunch break and I want to continue riding into the winter. The temperature hasn't been a problem so far (today it was 20 Deg) and I think I've got the clothing gear sorted out. So far, we haven't had any snow and the Roubaix has been great.
What I need are some recommendations for when we start getting snow, sand, ice, etc. I think my Roubaix, with its skinny road tires, will no longer be appropriate. I'm not planning on riding in blizzard conditions, but do hope to ride inbetween the storms where I might run into patches of packed snow, ice and sand. I'm thinking about picking up a used hybrid with twist shifters (good for bulky gloves) and knobby tires for approx $200. Does that make sense? Any particular models I should look at (I do want to keep it relatively light). Any other suggestions on the configuration?