Precipitation—mostly rain—will spread into the Southeast on Friday and affect portions of the Atlantic Coast States early in the weekend.  Meanwhile, sprawling Pacific storminess will slowly translate eastward, with a low-pressure system crossing the northern Plains and upper Midwest late in the weekend.  Cold air trailing that system could result in another round of temperatures below 0°F on Sunday and Monday in parts of Montana.  Meanwhile, blizzard conditions across the northern and central Sierra Nevada should persist into Sunday, with a broader area of the western U.S.

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