During the next several days, a sharp, north-to-south temperature gradient will become established across the country, with frigid conditions across the northern Plains and upper Midwest contrasting with warmth in the South.  Following an initial storm system expected to cross the upper Great Lakes region late Friday or early Saturday, several disorganized disturbances will produce widespread cloudiness but only light precipitation.  Some of the heaviest rain, locally 1 to 3 inches or more, will fall early next week in the Tennessee Valley and environs. 

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