In May, Denver saw 3.57 inches of rain, nearly double last year's 1.7 inches — and more than Seattle, according to the National Weather Service. But the high level of moisture isn't stopping the sun from coming out. Denver is projected to hit 100 degrees on consecutive days the weekend of July 21.
Those who feel like Denver is trending hotter as time goes on are correct. Data from the NWS shows four of the five hottest summers on record in Denver occurred within the last five years. Last year was the second-hottest summer in Denver's history.
Additionally, of Denver's ten coolest summers, the most recent was in 2004, when the average temperature was just 67.9 degrees Farenheit, amounting to the tenth coolest summer on record in Denver.
The coolest summer recorded by the NWS took place in 1915. That year, the average temperature was 65.8 degrees.
On the other hand, Denver has always been prone to summer heat, with some of the city's warmest summers occurring as early as the 1930s. Though it isn't yet entirely clear what 2025 will bring, the Old Farmer's Almanac predicted a very hot summer for almost the entire country, including Colorado. The Farmer's Almanac isn't a scientific publication, but the NWS also projected that temperatures in June, July and August would likely be high nationally.
A man pours water over his head during a summer day in 2006, the ninth-hottest on record in Denver.
Denver Library Archive/Evan Semón
In Colorado, the eastern half of the state has a 50 to 60 percent chance of above normal temperature, while the western half has a 60 to 70 percent chance of high temperatures during that time. However, most of those high temperatures are predicted to come later in the summer as the NWS determined that parts of Colorado would have an equal chance to be above or below normal temperatures in June.
If summer 2025 is going to be a hot one, we likely haven't gotten there yet. To rank as one of the ten hottest summers in Denver history, the average temperature from June through August would have to be 73.8 degrees or higher. With the summer solstice hitting today, June 20, here are the most intense we've recorded so far.
Ten Hottest Summers on Record in Denver:
1. 2012: average temperature of 76.3 degrees2. 2024: average temperature of 75 degrees
3. 2020: average temperature of 74.9 degrees
4. 2022: average temperature of 74.8 degrees
5. 2021: average temperature of 74.6 degrees
T-6. 1994: average temperature of 74.1 degrees
T-6. 1934: average temperature of 74.1 degrees
8. 1936: average temperature of 74 degrees
9. 2006: average temperature of 73. 9 degrees
10. 1980: average temperature of 73.8 degrees
