I saw -40*F with the wind chill at the top of Killington ski mountain in Vermont in '93 or '94. The exercise kept me from turning into a Popsicle but it was sure cold. I was glad to finally get down to the bottom, my bandanna over my face was a frozen stiff board that I had to crack in half to take off. I have never worked in that kind of weather. Mostly it is in the 20's (Fahrenheit), sometimes in the teens, seldom in the single digits and rarely below zero. All my chainsaw activity in winter is limited to storm cleanup of only what's necessary.