Just remember to drive slow, keep at least double space distance from other cars, and don't accelerate or brake hard. Be extra careful with on and off ramps, and also going over and under bridges. You'll be fine as long as you don't drive crazy. Born and raised in MN and moved east a couple years ago. I never owned a winter tire when I lived there. If you want the peace of mind, then go for it. I recommend after the first snow or two that you go to a big Walmart or Target late at night and "test drive" the car in the parking lot before it is all plowed to get a better feel for winter driving. The natural driving habits of most Prius owners will make them decent winter drivers.