On one (daytime) return flight in winter in that crisp cold air we questioned the controller of Mirny (that place with those enormous large surface diamond mines
https://en.wikipedia.org/wiki/Mir_mine ) what the local temp was at the moment. He said -35, where upon we woooowed in a reply from our comfortable cockpit, sipping coffee. Then he kinda shrugged and said that they thought it was real cold when temps started getting below -50....
read this one about living in Yakutsk, a "bit" further to the NE:
Yakutsk: Journey to the coldest city on earth | Europe | Travel | The Independent