For Tuesday, a low-pressure system traversing the middle Atlantic Coast, with precipitation—including wet snow—gradually ending from the central Appalachians into southern New England.  Subsequently, a period of relatively tranquil weather will prevail, with cool—but not frigid—weather across the North contrasting with mild conditions farther south.  By Friday, temperatures may dip below 0°F along the Canadian border from Montana to Minnesota.  During the mid- to late-week period, occasional snow will affect the northern U.S., starting on Wednesday in the Northwest. 

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