A storm system emerging from the western U.S. will drift eastward, crossing the nation’s mid-section by mid-week and reaching the East by Friday. Summer-like warmth will precede the storm, while cooler air will follow. Late-week freezes will affect the nation’s northern tier, including portions of the northern Plains, upper Great Lakes region, and New England. Storm-total precipitation could reach 2 to 4 inches or more from the southeastern Plains into the lower Midwest; locally severe thunderstorms may accompany the heavy rain.

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