A winter storm sweeping through the U.S. South on Tuesday was dumping snow at levels millions of residents haven’t seen ...

The polar vortex's blast of Arctic air from Canada brought the season's coldest weather to the majority of U.S. The vortex is ...

This blast of frozen temperatures is tied to a polar vortex... but what is that? Air spins around the notoriously cold North and South Poles. When the air is spinning fast, it's stable, but when it is ...

How Donald Trump's presidential inauguration unfolded as he was sworn in as the 47th President to succeed Joe Biden.