Least.... I did a job that had 5 hoods and 3 fans on the 7th floor of a hotel that sits on a lake the ambient temp was -20 with wind chill it was -50 below. Everything froze solid 4 times, try rolling up 150 foot of hose in -50 weather when your soaking wet, I froze as fast as the hose did LOL
Most any day above 12 deg. out I live at the top of the Upper Penninsula of Michigan, not much summer here