Frost/Freeze in San Juan River Basin, Colorado

There is no ASOS or AWOS available in this zone. The coldest temperature recorded at any RAWS site was 24F, at the San Juan Portable RAWS #2. The coldest temperature recorded at any site was 22F. Temperatures were at or below 32F for an average of 4.8 hours, with 5 of the 7 available sites seeing temperatures below 32F for any duration. The average time that temperatures at or below 28F were recorded was 3.5 hours, which marks this as a hard freeze event. No reports of crop losses or damages were recorded.

Clear skies and light winds in the wake of a low pressure system allowed temperatures to drop below freezing for many of the lower elevation valleys of southwestern Colorado. The growing season had been ongoing for around a month, with few freeze events prior to this. Some locations saw temperatures at or below 28F for at least 3 hours, marking this as a hard freeze event.