A storm system currently over the upper Great Lakes region will slowly weaken and drift northeastward.  Showers and thunderstorms along the Atlantic Coast should end by early Friday.  However, chilly conditions in the storm’s wake will linger, especially across the northern U.S.  For example, overnight temperatures near 10°F will persist into early next week across snow-covered portions of the northern Plains.  Meanwhile, additional freezes will occur as far south as central High Plains.  Late in the weekend and early next week, a new storm system will cross the northern U.S., delivering additional snow. 

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