[Bicycle Bob]

Welcome, southern neighbor! BTW, my 'phone up here in Spiritwood is local to Regina, thanks to the wonders of the 'net.
Winter mileage goes down due to thicker air, use of "choke" or equivalent, more rolling resistance and other factors. Depending on the temperature, I use a block heater for up to 3 hours, and then drive very gently until the engine is coming up to normal operating temperature.
A ten minute run sounds like a real car killer. I'd switch to a bicycle. No kidding, I've commuted year round in Winnipeg, and the summers are the worst. There are a few special techniques involved, though.