21.   Snow will be common along west-facing slopes from the Northwestern states to the central Rockies as brisk high-level winds import moist air from over the Pacific.

22.   Winds across southern California will shift later Friday and Friday evening, blowing from the north-northeast and thereby helping to import chillier air into the region.

23.   Wintry chill will persist from the upper Midwest to the Northeast on Thursday as jet stream winds continue to import Arctic air from central Canada.