For Thursday, rain will spread northward across the eastern U.S.  Some of the heaviest rain, 1 to 3 inches, will fall along the northern Atlantic Coast, leading to possible flooding.  Meanwhile, a storm system emerging from the western U.S. will cross the central and southern Plains on Thursday and Friday before reaching the Great Lakes region during the weekend.  Hazards associated with the trailing storm may include heavy rain and locally severe thunderstorms.  The most significant threat of severe weather will begin late Thursday across the southern Plains and extend eastward across the South on Friday into Saturday. 

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