Another month of unusually warm temperatures cemented September as the , and the , according to the National Weather Service.
Denver’s average temperature last month was 69.2 degrees, more than four degrees above the city’s normal September average of 64.8 degrees and just short of the 70-degree record set in 2024, . The coldest September average on record was 54.7 degrees in 1912.
Warmest September averages in Denver
- 70 degrees in 2024
- 69.4 degrees in 2015
- 69.3 degrees in 2019
- 69.2 degrees in 2026
- 69 degrees in 2022
Despite the warmth, roughly 2.23 inches of precipitation fell in the city in September, weather service meteorologists said. None of it was snow, marking Denver’s sixth snowless September in a row.
Denver has only seen measurable snowfall once in September in the last 20 years, with 1 inch of powder stacking up in 2020, according to weather service records. The city documented traces of snow in 2014 and 2012, but the rest of Denver’s Septembers since 2006 have been snowless.
On average, Denver sees 1.35 inches of September precipitation, according to the weather service.
Snowiest Septembers on Denver record
- 17.2 inches in 1971
- 16.5 inches in 1936
- 12.9 inches in 1959
- 11.4 inches in 1895
- 8.7 inches in 1985
In 2026, Denver has also logged its hottest March on record, its third-warmest February, its second-warmest July and its fourth-warmest August, according to weather service data. Denver broke more than a dozen heat records in March alone.
