Aspen climate

Aspen Weather in September

NOAA 1991-2020 normals for Aspen 1SW, 1.9 km from Aspen

Average highs run from 71°F on September 1 to 62°F on September 30, and lows from 44°F to 35°F. Normal precipitation for the month is 1.89 in over about 10 wet days.

September day by day

The normal high and low for each date, and the record, in °F.

Normal daily high and low temperature at Aspen, in °F, with the record for each date.020406080100151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
67°F
Average low
40°F
Precipitation
1.89 in
Snowfall
1.0 in
Record high
89°FSep 3, 2019
Record low
17°FSep 29, 1999
Chance of a freeze
79%
Daylight
13 h 02 min to 11 h 48 min
Cloud cover
48%
Humidity
57%
Dew point
28°F
Wind
4.9 mph

Every day of the month

A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.

DateNormal highNormal lowRecord highRecord lowChance wetChance of snow
Sep 171°F44°F87°F 201936°F 201037%1%
Sep 271°F44°F87°F 201936°F 201036%1%
Sep 370°F44°F89°F 201935°F 201036%1%
Sep 470°F44°F87°F 201733°F 200836%1%
Sep 570°F43°F88°F 202031°F 199936%1%
Sep 670°F43°F88°F 202234°F 200836%1%
Sep 769°F43°F88°F 202230°F 201036%2%
Sep 869°F42°F86°F 202230°F 200135%2%
Sep 969°F42°F86°F 202128°F 200135%2%
Sep 1069°F42°F87°F 202131°F 200135%2%
Sep 1169°F42°F83°F 202128°F 201035%2%
Sep 1268°F41°F82°F 201732°F 201035%2%
Sep 1368°F41°F83°F 202629°F 200335%2%
Sep 1468°F41°F85°F 200027°F 200334%2%
Sep 1567°F40°F84°F 201828°F 200434%3%
Sep 1667°F40°F83°F 200030°F 200634%3%
Sep 1767°F40°F82°F 201826°F 200634%3%
Sep 1866°F39°F82°F 201824°F 200333%3%
Sep 1966°F39°F81°F 201627°F 200333%3%
Sep 2066°F39°F80°F 201431°F 200233%4%
Sep 2165°F38°F78°F 201528°F 202133%4%
Sep 2265°F38°F78°F 201628°F 200932%4%
Sep 2365°F38°F78°F 201531°F 200032%4%
Sep 2464°F37°F79°F 201525°F 200632%5%
Sep 2564°F37°F79°F 200122°F 200032%5%
Sep 2664°F37°F79°F 201423°F 201731%5%
Sep 2763°F36°F80°F 201425°F 199931%5%
Sep 2863°F36°F78°F 200119°F 199931%6%
Sep 2963°F36°F79°F 202417°F 199931%6%
Sep 3062°F35°F77°F 200126°F 200731%6%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Aspen, in percent, and of at least 0.1 inch of snowfall.0102030401102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (MDT).

September 1
sunrise 6:36 AM, sunset 7:38 PM
September 30
sunrise 7:03 AM, sunset 6:51 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00050372 (Aspen 1SW), public domain. Records: NOAA GHCN-Daily, station USW00093073, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.