Cold air across the eastern half of the U.S. will retreat, with much warmer weather arriving late in the week and during the weekend.  In fact, weekend high temperatures will approach or reach 90°F across the central and southern Plains.  Cool conditions will linger, however, along the Atlantic Seaboard, where a coastal storm system may result in cloudiness and showers.  Meanwhile, a dramatic pattern change will commence on Friday in the Northwest, where cooler weather will accompany widespread rain and snow. 

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