The Cheyenne Office of the National Weather Service is warning people about dangerously cold wind chills for New Year's Eve (Dec.31).

The service issued this warning Sunday evening:

"Temperatures will fall dramatically into the single digits late Monday morning into early afternoon along with scattered snow showers occurring across the region. Wind chills will become negative by mid-morning and remain below zero through the rest of the day as snow tappers off. Temperatures will range from +5 to -10 with wind chills -25 to -10 across the entire region at midnight tomorrow night. See attached graphic. Wind Chill Advisories are now in effect for many portions of the area to highlight this hazard.
New Year's Day (Tuesday) low temperatures will be negative across the entire region, ranging from near -3 in the Nebraska High Plains to -20 near Rawlins. A slow warm up is expected through the rest of the week with above normal temperatures likely late week."