September · United States
Best time to visit Aspen in September Weather, crowds & prices
Weather in Aspen in September
Average temperature 9°C, 34 mm of rain, about 23 days with 6+ hours of sunshine and 53% humidity — based on the five most recent complete years of ERA5 data (2021–2025).
September score
1.7/10
Ranked #12 of 12 months
- Avg temp
- 9°C
- Rainfall
- 34 mm
- Humidity
- 53%
- Days with 6h+ sun
- 23
- Crowd Density
- Quiet / Uncrowded
- Average Expenses
- $ · Budget Friendly ($)
September in Aspen scores 1.7/10 for snow and ski travel - ranked #12 of 12. Expect around 9°C, 34 mm of rain, and roughly 23 days with 6+ hours of sunshine this month.
Aspen-gold slopes and Roaring Fork valley feel finest in December-March for snow, June-September for trails.
September in Aspen — off-season conditions
Expect 9°C (48°F) in September. A good month for city streets, viewpoints and long meals; leave swimming for another season.
With around 34 mm of rain, any showers tend to pass through rather than settle in; about 23 days with 6+ hours of sunshine and 12.2 hours of daylight fill the rest.
That is 1.7/10 on the same scale — 12th of 12 months, versus 9.5/10 for the best month here.
Pack a mid-weight jacket, long sleeves and shoes you can walk 15 km in.
Budget for low-season pricing, and crowds are light for this destination.
If your dates are flexible, April is materially better in Aspen — 7.8 points higher on the same scale.
Frequently asked
- What is the weather like in Aspen in September?
- In September, Aspen averages 9°C, 34 mm of rain, and about 23 days with 6+ hours of sunshine. Its climate-comfort score is 1.7/10.
- Is September a good time to visit Aspen?
- September earns a 1.7/10 climate-comfort score. Use the year-round chart to weigh the weather against your budget and crowd preferences.
- How much does it rain in Aspen in September?
- Expect about 34 mm of rain in September. Average humidity is 53% and there are about 23 days with 6+ hours of sunshine.
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