A sharp cold front driving southward from the Canadian Prairies will delineate the boundary between record-setting warmth to the south and east from markedly cooler weather farther north and west.  The front, which will also be preceded and accompanied by widespread precipitation, including locally severe thunderstorms, will stretch from the Great Lakes States to the southern Plains by late Tuesday and drive eastward to the Atlantic Seaboard by late Wednesday or early Thursday.  However, the post-frontal cool spell will be short-lived, with warm weather expected to return late in the week across the nation’s mid-section before expanding eastward. 

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