Portland, Portland, Oregon, United States Historical Air Quality Analysis
Dive into detailed Air Quality Insights with historical data, monthly patterns, and yearly trends at your fingertips!
July Air Quality Analysis
Portland, Portland, Oregon, United States
AQI Trends: Highest and Lowest
Same Day Analysis (31st July ):
On this day, AQI across the 4 years varied significantly: 2025 ranks 1st highest AQI at 19 of Good air quality on the same day.
Download 2024 Annual Data
World Air Quality Report
2025 Days Vs Air Quality
Portland, Portland, Oregon, United States
92%
166
8%
14
0.5%
1
Total number of days with different AQI categories in last 182 days in 2025 (183 days remaining)
Under WHO’s Safe Air Quality Limits: 92%
Health Risk Level:
Very Low
In 2025, 92% of 182 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
Portland, Portland, Oregon, United States
AQI levels in 2025
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
31AQI
24AQI
25AQI
23AQI
23AQI
24AQI
27AQI
33AQI
32AQI
37AQI
22AQI
29AQI
41AQI
50AQI
53AQI
50AQI
47AQI
32AQI
48AQI
41AQI
56AQI
55AQI
51AQI
44AQI
36AQI
33AQI
33AQI
46AQI
56AQI
75AQI
39AQI
21AQI
25AQI
25AQI
38AQI
34AQI
28AQI
31AQI
27AQI
47AQI
31AQI
25AQI
23AQI
23AQI
28AQI
36AQI
25AQI
20AQI
22AQI
19AQI
21AQI
23AQI
25AQI
18AQI
23AQI
21AQI
26AQI
23AQI
38AQI
39AQI
23AQI
24AQI
42AQI
67AQI
105AQI
89AQI
100AQI
100AQI
84AQI
68AQI
60AQI
52AQI
46AQI
38AQI
33AQI
29AQI
25AQI
23AQI
20AQI
19AQI
21AQI
20AQI
20AQI
20AQI
21AQI
17AQI
18AQI
17AQI
19AQI
17AQI
19AQI
18AQI
20AQI
23AQI
19AQI
26AQI
16AQI
17AQI
15AQI
19AQI
16AQI
16AQI
17AQI
17AQI
17AQI
19AQI
17AQI
20AQI
20AQI
18AQI
17AQI
16AQI
23AQI
29AQI
38AQI
29AQI
25AQI
15AQI
18AQI
20AQI
30AQI
28AQI
16AQI
17AQI
20AQI
23AQI
24AQI
18AQI
28AQI
29AQI
16AQI
20AQI
17AQI
23AQI
19AQI
20AQI
18AQI
16AQI
18AQI
11AQI
15AQI
24AQI
19AQI
18AQI
19AQI
17AQI
20AQI
25AQI
16AQI
19AQI
22AQI
19AQI
23AQI
27AQI
16AQI
17AQI
20AQI
22AQI
38AQI
36AQI
38AQI
40AQI
34AQI
22AQI
21AQI
22AQI
25AQI
23AQI
16AQI
16AQI
18AQI
19AQI
18AQI
22AQI
29AQI
27AQI
19AQI
16AQI
17AQI
19AQI
23AQI
39AQI
27AQI
41AQI
20AQI
20AQI
23AQI
No. of days
202529AQI
Highest AQI recorded in
March41AQI
Lowest AQI recorded in
April20AQI
202423AQI
Highest AQI recorded in
November32AQI
Lowest AQI recorded in
May16AQI
202325AQI
Highest AQI recorded in
August36AQI
Lowest AQI recorded in
April16AQI
202228AQI
Highest AQI recorded in
October53AQI
Lowest AQI recorded in
May15AQI
202127AQI
Highest AQI recorded in
March38AQI
Lowest AQI recorded in
May18AQI
202036AQI
Highest AQI recorded in
September115AQI
Lowest AQI recorded in
June15AQI
Most & Least Polluted Years Over the Last 6 Years
Portland's annual 2025 AQI (29) shows an average percentage change of 5.3% (worsened AQI) compared to previous years: 2020 (36), 2021 (27), 2022 (28), 2023 (25), 2024 (23).
