The National Weather Service says the cold snap could last up to a week.
The agency is urging everyone to be prepared for a winter storm, with a new winter weather warning in effect for the Washington, D.C. area.
It’s not clear if the weather will develop into a snowstorm or not, but the National Weather Forecast Office has issued a Winter Weather Advisory.
The weather advisory is not just for Washington, though.
It also applies to Oregon, Nevada, Colorado, Arizona, and Utah.
Here’s the full list of states and counties affected by the winter weather: