Mild, downsloping winds—the so-called Chinooks—were in fine form late Thursday, roaring out of the Montana mountains and the Black Hills of western South Dakota. Wind advisories were issued for gusts to 70 m.p.h. The mild air these powerful winds are delivering to the northern Plains Friday is headed for Chicago. Temperatures may flirt with 50° this weekend. Of all the Decembers since 1990, only 2000 failed to produce at 50° high. Readings at such mild levels are hardly a novelty this month. In 134 years of official weather observations, 111 (83%) of them have generated December 50s.
It’s snow making news in the Upper Midwest. Snowfalls reached 6” near Duluth—that area’s first major accumulation this season (a storm last week whitened areas farther east in northern Wisconsin and the Upper Peninsula). Nearby International Falls reported its first sub-0° (-4°) this season.
-Tom Skilling
