Precipitation will persist in the Pacific Northwest, with several more days of lingering rain and snow showers.  Late in the week, somewhat cooler air will trail the Northwestern storminess, with those cooler conditions also covering the remainder of the western U.S. and eventually reaching the nation’s mid-section.  Meanwhile, mild weather will continue nearly nationwide for the remainder of the week, aside from a brief spell of seasonably cold weather in the Midwest and Northeast.  Elsewhere, warmth across the Plains should peak on Wednesday or Thursday, with temperatures expected to top 70°F as far north as the central High Plains. 

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