A storm system currently arriving in the Pacific Northwest will traverse the nation’s northern tier. By mid-week, a significant wind-driven snow event may unfold across the north-central U.S., particularly in the Red River Valley. Starting on December 23, showers and thunderstorms along the storm’s trailing cold front will sweep eastward from the Mississippi Valley, reaching the Atlantic Seaboard on Christmas Eve.

In the Northeast, heavy rain falling upon melting snow may result in flash flooding.

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