A cold weather regime across the Northwest, northern Plains, and upper Midwest will further deepen as the week progresses. In fact, temperatures near or below 0° may occur toward week’s end across northern sections of the Rockies and High Plains.

Periods of precipitation, including widespread snow, will accompany the cold outbreak. In contrast, dry weather will prevail during the next 5 days from California to the southern half of the High Plains.

Much of that region will experience unusually warm weather, but colder air will drive southward late in the week across the Plains.

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