Frost/Freeze in Lower Yampa River Basin, Colorado

As four of the nine reporting stations available for verification recorded temperatures at or below 32F for at least 3 hours, at least 50% of the zone experienced a freeze. Only two of the nine stations recorded temperatures at or below 28F for at least 3 hours, so this was not a season ending freeze for the zone. The lowest temperature recorded was 22F, while the lowest recorded at the K4V0 AWOS in Rangely was 29F. Minimum temperatures ranged from 22F to 32F. Temperatures at or below 32F lasted for on average 3 hours, with a maximum of 10 hours and a minimum of 0. Temperatures at or below 28F lasted for on average 1 hour, with a maximum of 5 hours and a minimum of 0.

A weak cold front ushered in a shallow pool of cold air to the northwestern Colorado valleys on the afternoon and evening of October 24th. As skies began to clear in the wake of the front, radiational cooling kicked in, helping the already cold temperatures to drop even further. Under this regime, two of three zones under a Freeze Warning dropped below 28F long enough to experience a season ending freeze.