May in Greeley averages a daily high of 23.7°C with nights around 6.9°C. Expect roughly 10.7 wet days totalling 74.1mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Greeley is September–October.
Based on GREELEY UNC, CO US (2.5km), 1995–2024. 29 years of May data.