Millions of Americans will be under the threat of two rounds of severe weather, including tornadoes, this week, with the risk ...

Tornadoes can occur all around the world and have been recorded in all Canadian provinces and as far north as the Canadian arctic. In fact, Canada is the world's second-most tornado-prone country.

Fast-forward more than 70 years, and people receive alerts on their phones when there is a tornado threat for their precise location. Here are 10 facts about some of the biggest, strongest and ...