September · United States
Best time to visit Denver in September Weather, crowds & prices
Weather in Denver in September
Average temperature 19°C, 26 mm of rain, about 29 days with 6+ hours of sunshine and 44% humidity — based on the five most recent complete years of ERA5 data (2021–2025).
September score
9.9/10
Ranked #1 of 12 months
- Avg temp
- 19°C
- Rainfall
- 26 mm
- Humidity
- 44%
- Days with 6h+ sun
- 29
- Crowd Density
- Moderate Crowds
- Average Expenses
- $$$ · Peak Season Rates ($$$)
September in Denver scores 9.9/10 for sightseeing and cultural travel - the single best month of the year. Expect around 19°C, 26 mm of rain, and roughly 29 days with 6+ hours of sunshine this month.
Mile-high parks, craft breweries, and Front Range day trips peak May through September.
September: the best month of the year in Denver
September averages 19°C (67°F) — pleasant for mornings and evenings on foot in the city, with a midday break when the sun is strongest.
Expect 26 mm of rain — occasional showers rather than washed-out days — alongside about 29 days with 6+ hours of sunshine and 12.4 daylight hours.
On our climate-comfort scale this is the top-ranked month of the year for Denver at 9.9/10 — the reference point every other month on this page is measured against.
Pack light clothing, a hat and real sun protection.
Plan for peak pricing, with crowds are moderate. You are paying the year's highest rates for the year's best conditions — book early or shift a few weeks either side.
Frequently asked
- What is the weather like in Denver in September?
- In September, Denver averages 19°C, 26 mm of rain, and about 29 days with 6+ hours of sunshine. Its climate-comfort score is 9.9/10.
- Is September a good time to visit Denver?
- September earns a 9.9/10 climate-comfort score. Use the year-round chart to weigh the weather against your budget and crowd preferences.
- How much does it rain in Denver in September?
- Expect about 26 mm of rain in September. Average humidity is 44% and there are about 29 days with 6+ hours of sunshine.
Curated in Denver
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Denver, United States. Live activities and tours from GetYourGuide, matched to this destination.