PM Update: Hard Freeze Tonight

Continued sunny and cool tomorrow

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Despite brilliant sunshine today, temperatures have been a good 10 degrees colder than yesterday thanks to a steady southward stream of Canadian air. Highs so far have been right around 50 -- where they should hold for the next couple of hours before starting their steep evening descent...

Tonight: Cold Canadian air, light winds and clear skies...and you've got your recipe for a very cold early-spring night. Everyone's going below freezing tonight -- with some of the cold spots like Sterling, Va. and Clarksburg, Md. dropping all the way down into the low 20s. Inside the beltway, lows will be in the upper 20s to around 30.

Tomorrow (Tuesday): Bundle up for a mid-winter like morning commute to work. The spring sun will then go to work, but a high of 50 will probably be the best we can do given the frosty origins of the air overhead.

See Jason Samenow's full forecast through early next week, and follow CWG on Twitter and Facebook.

Rapid Change in Rapid City, South Dakota: Yesterday at this time, temperatures in Rapid City were in the mid-70s. Now, the town is under a Blizzard Warning with a foot or more of snow expected and 40-65 mph winds. This makes some of our recent temperature swings look wimpy.