We work and play regularly down to -30.
Anything colder than that we just call it a dog day and wait a day or two for the cold snaps to pass over us.
At these temps the diesels run fine but colder than this it seems to be when problems seem to pop up with fuel, hoses, maintaining engine temps, etc..
the snow is not going anywhere at those temps.... it can wait for another day to be cleared is my opinion.
I guess we just get used to where we live. Cold no problems but heat and humidity is more of a problem for me. I can always put on another layer whereas working naked is just plain rude.