I spent a whole winter in mongolia in 1989/90 and was very surprised at how the conditions varied to those in the UK. Here in the UK winter temperatues of around freezing can be quite unpleasant. In Mongolia temperature regularly were at -40°C and whilst it was undeniably cold there was little or no increase in the unpleasantness in comparison to the UK. The difference is humidity. In the UK the humidity is high but in Mongolia it is low. They rarely have slush as a by product of snow unlike the UK.
Someone I was with had experianced temperature of below -50°C at the airport in UB. Apparently moisture would form in the air in the shape of crystals when you exhaled.