(CNN) -- A storm that set snowfall records in Chicago has set its sites on Washington, D.C. and triggered over 1,000 flight cancellations to and from airports in its path.
Just west of the nation's capital, it could dump up to 20 inches of snow but may turn into a rain shower as it passes through, according to a National Weather Service bulletin early Wednesday.
The federal government has closed offices for Wednesday. Emergency personnel will be expected to work as well as those equipped to work from home. D.C. schools will also be closed.
Washington suburb Arlington, Virginia, has readied snow plows and trucks in case of major snowfall.
Airlines have canceled flights to and from Washington's Dulles airport ahead of the storm's arrival: United 650, U.S. Airways 350, American 20.
In its wake, the storm has left about a foot of snow in parts of Illinois, Minnesota and North Dakota and paved a white swath through across the Upper Midwest.
Nearly 30,000 customers have lost electricity.
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