Frost/Freeze in Debeque To Silt Corridor, Colorado

With an unusually cold airmass in place, and calm winds and clear skies promoting effective radiational cooling, temperatures dropped below freezing across much of the zone. 7 of the 10 sites available recorded temperatures at or below 32F for at least 3 hours, with the average duration of these temperatures being 5 hours. Only 3 sites recorded temperatures at or below 28F for at least 3 hours, with an average duration being 2.5 hours. The lowest temperature recorded was 22F at a Colorado State Agricultural Mesonet station. The KRIL ASOS at the Garfield Regional Airport in Rifle, CO recorded a minimum temperature of 28F. Minimum temperatures ranged from 22F to 32F, with an average minimum of 29F. This event qualifies as a general Freeze, but not a Hard Freeze.

A potent shortwave trough drove a strong cold front through eastern Utah and western Colorado during the day prior to the freeze event, with unseasonably cold air filtering in behind the front. This in combination with light winds and clear skies allowed temperatures to fall several degrees below normal for early May, including below freezing in many agricultural parts of the region where the growing season was already well underway.