Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
As August makes way for September, Aspen's average high-temperature eases from an enjoyable 67.3°F (19.6°C) to a still refreshing 61°F (16.1°C). Despite the hot September days, Aspen's nights see an average temperature plunge to a cold 34.5°F (1.4°C).Humidity
The average relative humidity in September is 59%.Rainfall
The month with the least rainfall is September, when the rain falls for 5.5 days and typically collects 0.2" (5mm) of precipitation.Snowfall
January through June, September through December are months with snowfall. September is the first month it typically snows. Throughout September, in the average 1.1 snowfall days, it receives 0.08" (2mm) of snow. In Aspen, Colorado, during the entire year, snow falls for 83.2 days and aggregates up to 19.45" (494mm) of snow.Daylight
In September, the average length of the day in Aspen is 12h and 26min.On the first day of the month, sunrise is at 6:36 am and sunset at 7:37 pm. On the last day of September, sunrise is at 7:03 am and sunset at 6:50 pm MDT.
Sunshine
In Aspen, the average sunshine in September is 10.9h.UV index
In Aspen, the average daily maximum UV index in September is 3. A UV Index value of 3 to 5 symbolizes a medium health hazard from unsafe exposure to UV radiation for the average person.Note: A maximum high UV index of 3 in September translates into the following recommendations:
Guard yourself - An obligation to protect skin and eyes from harm exists. The Sun's UV radiation is especially harmful around midday, so reduce exposure and stay safe. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes. Be alert! Nearly double the UV rays from the Sun can be reflected by snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the temperature in September in Aspen?
What is the average humidity in September in Aspen?
What is the driest month in Aspen?
How many days does it rain in September in Aspen?
When does it start snowing in Aspen?
What is the average length of the day in September in Aspen?
When are sunrise and sunset in September in Aspen?
How many hours of sunshine does Aspen have in September?
What is the UV index intensity in September in Aspen?
Average temperature in September
Aspen, CO
- Average high temperature in September: 61°F
The warmest month (with the highest average high temperature) is July (69.4°F).
The months with the lowest average high temperature are January and December (24.4°F).
- Average low temperature in September: 34.5°F
The month with the highest average low temperature is July (40.5°F).
The coldest month (with the lowest average low temperature) is January (2.1°F).
Average pressure in September
Aspen, CO
- Average pressure in September: 30.06"Hg
The month with the highest atmospheric pressure is January (30.23"Hg).
The months with the lowest atmospheric pressure are April and May (29.95"Hg).
Average wind speed in September
Aspen, CO
- Average wind speed in September: 4.8mph
The windiest month (with the highest average wind speed) is June (6.2mph).
The calmest months (with the lowest average wind speed) are January and August (4.5mph).
Average humidity in September
Aspen, CO
- Average humidity in September: 59%
The month with the highest relative humidity is February (90%).
The month with the lowest relative humidity is June (51%).
Average rainfall in September
Aspen, CO
- Average rainfall in September: 0.2"
The wettest months (with the highest rainfall) are March and July (0.51").
The driest month (with the least rainfall) is September (0.2").
Average rainfall days in September
Aspen, CO
- Average rainfall days in September: 5.5 days
The month with the highest number of rainy days is July (12.1 days).
The month with the least rainy days is January (2.8 days).
Average snowfall in September
Aspen, CO
- Average snowfall in September: 0.08"
The month with the highest snowfall is March (3.98").
The months with the least snowfall are July and August (0").
Average snowfall days in September
Aspen, CO
- Average snowfall days in September: 1.1 days
The month with the highest number of snowfall days is February (12.8 days).
The months with the least snowfall days are July and August (0.1 days).
Average daylight in September /
Average sunshine in September
Aspen, CO
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in September: 10h and 5min
The month with the most sunshine is June (Average sunshine: 11h and 48min).
The month with the least sunshine is February (Average sunshine: 5h and 12min).
Average sunshine days in September
Aspen, CO
- Average sunshine days in September: 17.8 days
The month with the most sunshine days is November (23.6 days).
The month with the least sunshine days is July (9.8 days).
Average UV index in September
Aspen, CO
- Average UV index in September: 3
The months with the highest UV index are June, July and August (UV index 4).
The months with the lowest UV index are February and December (UV index 1).
Average cloud cover in September
Aspen, CO
- Average cloud cover in September: 17
The month with the most cloud cover is February (Cloud cover 53).
The month with the least cloud cover is June (Cloud cover 15).
Average visibility in September
Aspen, CO
- Average visibility in September: 6mi
The months with the highest visibility are May, June, July, August, September and October (6mi).
The months with the lowest visibility are January, February, March and December (4mi).
Aspen, Colorado, USA
Weather forecast for your location
2. Allow the app to use your location