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Climate · Aspen

Aspen in September

Warm and damp, as the days shorten.

Typical weather, averaged over 30 years

September in Aspen is warm: highs near 72°F, lows near 40°F. Rain falls on about three days a week, and the days shorten by 55 minutes from the first week to the last.September in Aspen is warm: highs near 22°C, lows near 4°C. Rain falls on about three days a week, and the days shorten by 55 minutes from the first week to the last.

High
72°F22°Caverage
Low
40°F4°Caverage
Wet days
3a week · 38% of days
Daylight
12h 22mon average

Is September a good time to visit Aspen?

Yes. September is one of Aspen's best months (June to September).

How we judge it: every month is scored on how close its typical high comes to the range from 70°F to 80°F, how mild its nights are, and how rarely it rains. The best months are the run of months that scores best.How we judge it: every month is scored on how close its typical high comes to the range from 21°C to 27°C, how mild its nights are, and how rarely it rains. The best months are the run of months that scores best.

How September sits in the year

week by week

Temperature

Highs near 72°F in September, against 34°F to 80°F through the year.Highs near 22°C in September, against 1°C to 27°C through the year.

Chance of a wet day

38% of days in September, against 28% to 51% through the year.

Cloud cover

28% cover in September, against 28% to 50% through the year.

Daylight

12h 22m in September, against 9h 27m to 14h 53m through the year.

Week by week, lightly smoothed, with September shaded. The olive line marks the best months. Hover or tap a week for its figures.

Either side

  1. August78°26°low 46°low 8°4 wet days a weekRain on about four days a week.
  2. September72°22°low 40°low 4°3 wet days a weekRain on about three days a week.
  3. October60°16°low 30°low -1°2 wet days a weekRain on about two days a week.

Where Aspen sits, in September

America/Denver
this place
typical high in September 40°F4°C95°F35°C
Sunrise, mid-September
6:47 AMsets 7:18 PM
Above the sea
2,410 mhigh country
Latitude
39.2°Nnorthern hemisphere
Nearest of ours
Crested Butte38 km south

The land around Aspen, shaded by its typical high in September, the planning map's own layer. Hover the map for the figure at that spot; tap it on a phone. Clock times are local, for the 15th.

Elsewhere in United States in September

high · low · wet days
See September on the planning mapThe whole year in Aspen

Typical weather, averaged over 30 years (1995–2024), from the 11 km grid square nearest Aspen. Temperatures are adjusted against 66 weather stations: daytime highs read about 3.1°F cold in the source data and are raised to match, and both highs and lows are adjusted for the town's height (2,410 m) against the climate model's (2,933 m).Temperatures are adjusted against 66 weather stations: daytime highs read about 1.7°C cold in the source data and are raised to match, and both highs and lows are adjusted for the town's height (2,410 m) against the climate model's (2,933 m). Daylight is calculated from latitude. Charts are lightly smoothed week to week; the figures in the table are not. Source: Copernicus ERA5-Land reanalysis; cloud cover from NASA's MERRA-2 reanalysis, on a coarser grid of about 50 km. Contains modified Copernicus Climate Change Service information 2026; neither the European Commission nor ECMWF is responsible for any use of it. These are averages, not a forecast.

Daylight is calculated from latitude. Charts are lightly smoothed week to week; the figures in the table are not.

Source: Copernicus ERA5-Land reanalysis; cloud cover from NASA's MERRA-2 reanalysis, on a coarser grid of about 50 km. Contains modified Copernicus Climate Change Service information 2026; neither the European Commission nor ECMWF is responsible for any use of it. These are averages, not a forecast.