Yacolt, Washington, United States Historical Air Quality Analysis
Dive into detailed Air Quality Insights with historical data, monthly patterns, and yearly trends at your fingertips!
September Air Quality Analysis
Yacolt, Washington, United States
AQI Trends: Highest and Lowest
Same Day Analysis (20th September ):
On this day, AQI across the 1 years varied significantly: 2025 ranks 1st highest AQI at 40 of Good air quality on the same day.
Download 2024 Annual Data
World Air Quality Report

Day & Night AQI Trend: 20th Sep - 21st Sep 2025
Yacolt, Washington, United States
6 AM20th Sep 2025
7 PM
5 AM21st Sep 2025
52AQI
38AQI
41AQI
32AQI
In the last 24 hours,
Yacolt's AQI reached its highest point of 52 at 4 PM during the Day, while the lowest point, 32, was recorded at 5 AM during the Night between 20th Sep and 21st Sep 2025.
Day & Night AQI Trend : Aug - Sep 2025
Yacolt, Washington, United States
28°C19/37°C
29°C22/38°C
27°C20/35°C
25°C20/32°C
25°C19/33°C
23°C18/30°C
23°C16/32°C
20°C15/28°C
19°C13/26°C
19°C15/24°C
18°C13/23°C
22°C14/32°C
22°C16/31°C
23°C16/32°C
21°C16/28°C
18°C16/20°C
19°C16/22°C
20°C13/28°C
20°C15/24°C
17°C12/23°C
16°C14/21°C
16°C13/22°C
17°C12/27°C
15°C10/18°C
17°C8/26°C
23°C18/30°C
20°C15/28°C
18°C12/26°C
19°C11/30°C
19°C12/27°C
--°C/°C
38AQI
36AQI
39AQI
39AQI
2025 Days Vs Air Quality
Yacolt, Washington, United States
98%
176
2%
3
Total number of days with different AQI categories in last 264 days in 2025 (101 days remaining)
Under WHO’s Safe Air Quality Limits: 98%
Health Risk Level:
Very Low
In 2025, 98% of 264 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
Yacolt, Washington, United States
AQI levels in 2025
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
19AQI
16AQI
17AQI
15AQI
22AQI
16AQI
17AQI
17AQI
19AQI
25AQI
21AQI
25AQI
14AQI
13AQI
15AQI
18AQI
16AQI
16AQI
23AQI
20AQI
24AQI
22AQI
22AQI
27AQI
22AQI
18AQI
14AQI
16AQI
18AQI
22AQI
31AQI
24AQI
16AQI
14AQI
17AQI
18AQI
21AQI
21AQI
13AQI
16AQI
15AQI
18AQI
18AQI
15AQI
20AQI
22AQI
15AQI
14AQI
14AQI
18AQI
17AQI
16AQI
14AQI
12AQI
14AQI
13AQI
15AQI
17AQI
16AQI
20AQI
21AQI
17AQI
16AQI
17AQI
14AQI
16AQI
20AQI
14AQI
16AQI
18AQI
17AQI
17AQI
19AQI
19AQI
28AQI
30AQI
26AQI
28AQI
26AQI
18AQI
18AQI
20AQI
20AQI
18AQI
16AQI
16AQI
15AQI
12AQI
13AQI
21AQI
35AQI
30AQI
17AQI
14AQI
13AQI
16AQI
20AQI
22AQI
16AQI
16AQI
17AQI
26AQI
21AQI
20AQI
24AQI
18AQI
16AQI
19AQI
21AQI
22AQI
19AQI
22AQI
23AQI
28AQI
25AQI
21AQI
22AQI
23AQI
24AQI
23AQI
21AQI
18AQI
17AQI
20AQI
20AQI
21AQI
25AQI
25AQI
28AQI
22AQI
21AQI
30AQI
38AQI
24AQI
17AQI
18AQI
21AQI
26AQI
29AQI
28AQI
30AQI
18AQI
15AQI
13AQI
16AQI
17AQI
18AQI
18AQI
18AQI
24AQI
32AQI
45AQI
50AQI
50AQI
48AQI
43AQI
41AQI
41AQI
40AQI
35AQI
40AQI
53AQI
49AQI
57AQI
57AQI
41AQI
32AQI
24AQI
37AQI
49AQI
28AQI
36AQI
23AQI
20AQI
25AQI
28AQI
24AQI
32AQI
40AQI
18AQI
19AQI
17AQI
20AQI
21AQI
28AQI
37AQI
No. of days
202523AQI
Highest AQI recorded in
September37AQI
Lowest AQI recorded in
May17AQI
Most & Least Polluted Years Over the Last 1 Years
Yacolt's annual 2025 AQI (23) shows an average percentage change of NaN% (improved AQI) compared to previous years: .