There are many reports in the Prophetic Sunnah which hail the practice of those who are keen to observe ablution in such harsh and very cold circumstances. However, Islam permits the Muslim to choose the easy option and the possible religious alternative (such as dry ablution in the case in question) in case one is faced with unbearable circumstances.
Thus, it is up to every devoted muslim to view their current state of affairs and the level of harm they may face as a result of performing ablution out in a very cold weather. Islam permits the Muslim to resort to ablution in case an irreparable harm maybe inflicted on him.