Snow-covered cattle stand in a field in Baxter County, Ark., on Feb. 9. Northern Arkansas received more than 12 inches of snow. Kevin Pieper/The Baxter Bulletin/AP
Stephen Schaefer jumps while swinging a broom to knock down icicles hanging from a roof in Hutchinson, Kan., on Feb. 9. Joel Prince/The Hutchinson News/AP
Dajia Reed (l.) and Tamaria Evans push the base of a snowman through their yard in Vicksburg, Miss., on Feb. 10. David Jackson/The Vicksburg Evening Post/AP
A cyclist rides through slick streets as heavy snow falls in Franklin, Tenn., on Feb. 9. Sanford Myers/The Tennessean/AP
Parhelia, also known as sundogs, hover over the Illinois River in Peoria, Ill., on Feb. 10. Sundogs appear as sunlight refracts through ice crystals in the atmosphere. Adam Gerik/Journal Star/AP
A person tries to dig out near Grove, Okla., on Feb. 9. Another powerful blizzard howled through the nation's midsection, piling up to two feet of new snow on parts of Oklahoma and Arkansas. Tom Gilbert/Tulsa World/AP
Lucio Mendez (r.) walks carefully down to his truck as he and his passenger wait for help to arrive along Alabama 24 in Russellville, Ala., on Feb. 10. Matt McKean/The Times Daily/AP
Icicles block the front door of a farmhouse on Jan. 24 in Canterbury, N.H., as temperatures drop below zero overnight. Jim Cole/AP
A horse with a frost-covered face stands in a pasture on Jan. 24, in Calais, Vt. Toby Talbot/AP
Pedestrians gawk at a car that was frozen under a sheet of ice after a water pipe broke nearby in New York on Jan. 24. Seth Wenig/AP
Ice sculptor Earl Anthony Morse works finishing touches for a Martini Ice bar in subfreezing temperatures at the Bedford Village Inn, on Jan. 24, in Bedford, N.H. Jim Cole/AP
A view of broken ice in the freezing waters of the Delaware River are seen near the Ben Franklin Bridge in Camden, N.J., on Jan. 23. Jose F. Moreno/Camden Courier-Post/AP
Ice fishing enthusiasts drive over frozen Lake Erie after marking a route to a popular fishing location with trees frozen in the ice during winter weather off the shore of Buffalo, N.Y., on Jan. 24. David Duprey/AP
A boat dock is shown in the frozen waters of the Delaware River in Camden, N.J., on Jan. 23. Jose F. Moreno/Camden Courier-Post/AP
A couple walks on the waterfront in the borough of Brooklyn after an overnight snow fall on Jan. 21 in New York City. The Manhattan skyline and Brooklyn Bridge are visible in the background. Peter Morgan/AP
A woman looks out over the frozen inner bay in the south end of New Bedford, Mass., on Jan. 24. Peter Pereira/The Standard Times/AP
A passenger sits in a taxi as it warms up at the Rensselaer Rail Station in Rensselaer, N.Y., on Jan. 24. Mike Groll/AP
A pair of mallard ducks fly down a stream in Oneonta, N.Y., on Jan. 24. Julie Lewis/The Daily Star/AP
Arctic air has driven down temperatures in most of the continental US. A new video animation from NOAA shows the arctic air swirling into the country and predicts its path.
If you live anywhere within the northern two-thirds of the United States, you've probably noticed that it's pretty chilly outside. The plunge in temperatures over the past few days comes courtesy of an invasion of Arctic air that has been captured in a mesmerizing new animation from the National Oceanic and Atmospheric Administration.
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