The Midwest, specifically Illinois, Wisconsin, North Dakota, and Minnesota, has been hit by a polar vortex, a particularly nasty blast of frigid weather. To say that it's freezing in these four states right now is putting it mildly, with Chicago and other cities in the region set to reach record-low temperatures. While residents of these four states are used to tough winters, the polar vortex takes being cold to a whole new level. 

People across social media have let it be known just how cold it's gotten, with temperatures reaching as low as minus 42 fahrenheit in Park Rapids, Minnesota. The National Weather Service has warned people in those regions to stay indoors, citing "life-threatening wind chills."

If you're not in the Midwest, don't breathe easily just yet. AccuWeather meteorologist Rob Richards told USA TODAY that even Atlanta could "receive a coating to an inch of snow." Speaking about the Midwest in particular, he added, “I cannot stress how dangerously cold it will be. An entire generation has gone by without experiencing this type of cold."

Chicago has taken a good brunt of the cold weather, and the city's residents have posted videos and photos on Twitter to highlight what they're currently experiencing. From frost indoors to boiling water instantly evaporating upon facing the cold air, this polar vortex is no joke. Check out scenes from the extreme cold spell below.