It's been really cold across much of the nation this week, and the winter weather's expected to continue through the weekend across much of the Midwest and East.
But right now, we just want to pass along this video from the National Oceanic and Atmospheric Administration, which shows how the cold air spread from last Saturday (Jan. 19) through Thursday. See if you agree with Discovery.com that it's mesmerizing.
NOAAVisualizations /YouTube
