A low pressure trough marched through Colorado followed by several short waves that pounded mid western states with historic low freezing temperatures. Most of the midwest is in a deep freeze, with many states experiencing historic low temperatures, snow and ice storms.
When the low set-up in Colorado, it took temperatures from mild highs in the low 60f temperature range, and within 36 hours plunged temperatures into frigid negative numbers. For example, the temperature drop was so rapid that the town of Lake George, near the Palmer Divide, and just east of South Park, went from 41f degrees on December 3rd down to -29f degrees on December 4th, a 70 degree drop in temperature in less than two days (See slideshow). The same was true of Buckley AFB near Denver showing a drop in temperatures from 57f degrees to -9 degrees, and Frasier, Colorado went from 32f degrees all the way down to -34 degrees on December 4th with wind gusts up to 20 mph for a combined deadly wind chill factor of approximately -68f degrees.
This sudden loss in temperature in the Colorado Front Range put a rapid demand for heating on utilities, and in Niwot, Colorado, when temperatures had dropped to nearly -9f degrees, many residents were suddenly without power and natural gas, and were urged to leave their homes and seek warm shelter.
Temperatures are not expected to rise appreciably above the low teens for most of the this week.