5 miles round trip.
61.2 deg North, long "used to be colder"winters and plenty of summer or fall rain.
Ride drop bar 29er with studded tires in winter or fat tire bike on deeper snow days.
Ride every single day because it is fun , the $ saving is just a bonus.
Most important part of bike commuting that people miss is being HYPER aware of your surroundings, distracted drivers, ice/snow conditions, mindless pedestrians, etc, etc.