Back in June, it felt like summer might never arrive. Despite a tardy arrival, though, Colorado’s summer finished warmer than average and considerably drier than average, .
Colorado finished with its 33rd-driest and 25th-warmest summer on record (out of 124 years of official records), all despite a significantly cooler and wetter than average month of June.
For record-keeping purposes, meteorologists consider the complete months of June, July and August collectively as the definition of summer. To be clear, that’s separate from astronomical summer, which officially ends on Sept. 23.
Temperature-wise, Colorado finished with a statewide three-month average temperature of 66 degrees, 1.5 degrees above the 1901-2000 mean. While 2018 was notably warmer overall, August was an especially warm month across the state. Colorado finished with an average August statewide temperature of 68.4 degrees, more than offsetting a cooler June.
The further west and south you went in Colorado, however, the drier and warmer you generally trended this summer. This was mainly due to a largely muted monsoon season, and that now has a large chunk of the state under abnormally dry conditions despite a wet winter and spring. Arizona — the state that typically receives the most monsoonal moisture — finished with its driest summer on record, and neighboring Utah, New Mexico and California all finished with their top-10 driest summers on record.
While western and southern Colorado largely finished with far below-average precipitation, parts of northern and eastern Colorado finished with above-average precipitation throughout the summer. Overall, Colorado finished with an average of 4.81 inches of rainfall statewide for the summer
In Denver, summer total rainfall came out to 5.24 inches, about a half-inch above the long-term average of 4.77 inches. The city also had an average summer temperature of 72.2 degrees, or about a degree and a half above the long-term June, July and August average of 70.7 degrees.
As far as fall is concerned, puts Colorado and much of the West in above-average chances for a warm and wet autumn.
