Aspen, Colorado, United States Historical Air Quality Analysis
Dive into detailed Air Quality Insights with historical data, monthly patterns, and yearly trends at your fingertips!
August Air Quality Analysis
Aspen, Colorado, United States
AQI Trends: Highest and Lowest
Same Day Analysis (4th August ):
On this day, AQI across the 5 years varied significantly: 2025 ranks 3rd highest AQI at 34 of Good air quality, showing improvement over 2024 and 2021 on the same day.
Download 2024 Annual Data
World Air Quality Report

Day & Night AQI Trend: 4th Aug - 5th Aug 2025
Aspen, Colorado, United States
5 AM4th Aug 2025
8 PM
4 AM5th Aug 2025
64AQI
30AQI
57AQI
24AQI
In the last 24 hours,
Aspen's AQI reached its highest point of 64 at 3 PM during the Day, while the lowest point, 24, was recorded at 5 AM during the Night between 4th Aug and 5th Aug 2025.
Day & Night AQI Trend : Jul - Aug 2025
Aspen, Colorado, United States
17°C6/24°C
15°C4/24°C
17°C7/26°C
19°C9/28°C
18°C10/25°C
17°C6/24°C
17°C4/25°C
15°C7/25°C
17°C7/25°C
17°C8/25°C
16°C7/23°C
14°C6/21°C
15°C6/23°C
17°C7/23°C
18°C9/24°C
16°C8/22°C
16°C8/22°C
16°C11/21°C
16°C6/22°C
15°C6/23°C
16°C7/24°C
17°C6/26°C
16°C8/26°C
16°C9/23°C
15°C6/24°C
14°C5/22°C
13°C5/21°C
14°C5/22°C
16°C6/24°C
17°C6/27°C
--°C/°C
31AQI
31AQI
30AQI
30AQI
2025 Days Vs Air Quality
Aspen, Colorado, United States
99%
213
1%
3
Total number of days with different AQI categories in last 217 days in 2025 (148 days remaining)
Under WHO’s Safe Air Quality Limits: 99%
Health Risk Level:
Very Low
In 2025, 99% of 217 days were within WHO’s safe air quality limits. The risk of health issues is Very Low, but health impacts are still unclear.
Annual Air Quality Insights
Aspen, Colorado, United States
AQI levels in 2025
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
25AQI
24AQI
25AQI
20AQI
20AQI
21AQI
22AQI
22AQI
19AQI
27AQI
21AQI
26AQI
44AQI
27AQI
24AQI
22AQI
25AQI
20AQI
20AQI
22AQI
24AQI
23AQI
22AQI
19AQI
20AQI
31AQI
33AQI
29AQI
28AQI
29AQI
33AQI
28AQI
20AQI
26AQI
26AQI
25AQI
31AQI
30AQI
22AQI
21AQI
21AQI
23AQI
22AQI
16AQI
16AQI
17AQI
14AQI
14AQI
14AQI
15AQI
16AQI
18AQI
17AQI
18AQI
18AQI
17AQI
18AQI
22AQI
28AQI
29AQI
29AQI
21AQI
14AQI
16AQI
12AQI
12AQI
14AQI
18AQI
25AQI
25AQI
19AQI
29AQI
57AQI
16AQI
16AQI
23AQI
22AQI
17AQI
20AQI
17AQI
16AQI
15AQI
18AQI
22AQI
28AQI
28AQI
26AQI
18AQI
29AQI
30AQI
19AQI
17AQI
17AQI
16AQI
14AQI
15AQI
21AQI
24AQI
32AQI
38AQI
30AQI
23AQI
20AQI
18AQI
22AQI
19AQI
19AQI
16AQI
14AQI
13AQI
14AQI
15AQI
16AQI
15AQI
16AQI
16AQI
18AQI
14AQI
13AQI
15AQI
14AQI
16AQI
15AQI
16AQI
14AQI
14AQI
15AQI
15AQI
15AQI
16AQI
17AQI
20AQI
21AQI
26AQI
15AQI
16AQI
14AQI
14AQI
16AQI
19AQI
15AQI
18AQI
20AQI
18AQI
17AQI
17AQI
17AQI
22AQI
17AQI
18AQI
19AQI
18AQI
18AQI
18AQI
20AQI
17AQI
17AQI
20AQI
21AQI
21AQI
22AQI
20AQI
20AQI
23AQI
22AQI
20AQI
22AQI
21AQI
20AQI
22AQI
29AQI
25AQI
23AQI
20AQI
21AQI
21AQI
22AQI
31AQI
31AQI
27AQI
23AQI
23AQI
23AQI
22AQI
22AQI
23AQI
22AQI
20AQI
21AQI
22AQI
27AQI
36AQI
30AQI
26AQI
24AQI
40AQI
57AQI
56AQI
48AQI
31AQI
25AQI
25AQI
22AQI
21AQI
33AQI
38AQI
33AQI
24AQI
25AQI
26AQI
31AQI
41AQI
32AQI
26AQI
21AQI
34AQI
25AQI
20AQI
22AQI
19AQI
17AQI
22AQI
30AQI
28AQI
No. of days
202522AQI
Highest AQI recorded in
July30AQI
Lowest AQI recorded in
May17AQI
202420AQI
Highest AQI recorded in
July37AQI
Lowest AQI recorded in
May9AQI
202321AQI
Highest AQI recorded in
July31AQI
Lowest AQI recorded in
January13AQI
202221AQI
Highest AQI recorded in
September29AQI
Lowest AQI recorded in
July17AQI
202126AQI
Highest AQI recorded in
August50AQI
Lowest AQI recorded in
May14AQI
202025AQI
Highest AQI recorded in
September43AQI
Lowest AQI recorded in
March9AQI
Most & Least Polluted Years Over the Last 6 Years
Aspen's annual 2025 AQI (22) shows an average percentage change of -0.3% (improved AQI) compared to previous years: 2020 (25), 2021 (26), 2022 (21), 2023 (21), 2024 (20).