Frost dates in Colorado
13 cities · typical last spring freeze → typical first fall freeze (32°F, median of 1991–2020 normals)
DenverMay 4 → October 8Colorado SpringsMay 3 → October 8AuroraMay 7 → October 8Fort CollinsMay 2 → October 7LakewoodMay 3 → October 7ThorntonMay 2 → October 11ArvadaMay 3 → October 14WestminsterMay 2 → October 11GreeleyMay 2 → October 8PuebloApril 30 → October 9CentennialMay 5 → October 8BoulderMay 6 → October 5LongmontMay 7 → October 5