Cold/Wind Chill in Upper Green River Basin, Wyoming

The ASOS at the Big Piney Airport set new record low temperatures of 15 below zero on November 12, and 18 below zero on November 13. Record low maximums were also recorded from November 11, 12, and 13, as temperatures only climbed to 15, 11, and 10 above zero, respectively.

Unseasonably warm air over Wyoming during the first nine days of November was quickly ushered out of the state on November 10. An air mass with origins in Siberia plunged south across western and central Wyoming and ushered in record cold temperatures. Casper set an all-time November record low temperature of 27 below zero on Wednesday, November 12. This reading also shattered the old monthly record by 6 degrees. Low temperatures of 10 below to around 25 below zero were common across the area. Many locations not only set record low temperatures but also daily records for the lowest maximum temperature.