Winter range when not plugged in?

For those who live in northern climates winter conditions , how is range affected when you have to park outside for 10 hours ( while at work ) and not be able to plug in your electric car? Last winter we had -40 C wind chill for weeks. I be able to have car plugged in my garage and pre-condition car.
What I am concerned about is whether severe cold while parked outside erase all range altogether? It is 8 kms to work from my home.

Most likely be looking at Smart Electric or BMW i3 as they are rwd based. Can not afford a Tesla.

Dan