Repeating a scenario that has played out frequently in recent days, Western storminess will shift eastward as the week progresses.  Around mid-week, a weak disturbance racing across the nation’s northern tier will produce some snow, mainly across the northern Plains and upper Great Lakes region.  Concurrently, scattered showers and thunderstorms will race eastward toward the middle Atlantic Coast.  Late in the week, a more substantial storm system will emerge from the Southwest.  That storm will cross the southern Plains on Thursday and reach peak intensity over the Midwest on Friday. 

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