4. Ottawa (Canada) -37C
Canadians are used to the cold, making the most of the frozen weather to play their national sport: ice hockey. Catch a game at Scotiabank Place, home of the Ottawa Senators - Ottawa's professional ice hockey team. If you're really keen, take to the ice yourself on the Rideau Canal, Ontario's first UNESO World Heritage Site, which winds its way through the city and is the world's largest naturally frozen skating rink come winter.