Portage Park, Chicago, Illinois, United States Historical Air Quality Analysis
Dive into detailed Air Quality Insights with historical data, monthly patterns, and yearly trends at your fingertips!
October Air Quality Analysis
Portage Park, Chicago, Illinois, United States
AQI Trends: Highest and Lowest
Same Day Analysis (25th October ):
On this day, AQI across the 1 years varied significantly: 2025 ranks 1st highest AQI at 69 of Moderate air quality on the same day.
Download 2024 Annual Data
World Air Quality Report

Day & Night AQI Trend: 25th Oct - 26th Oct 2025
Portage Park, Chicago, Illinois, United States
6 AM25th Oct 2025
6 PM
5 AM26th Oct 2025
66AQI
43AQI
84AQI
54AQI
In the last 24 hours,
Portage Park's AQI reached its highest point of 84 at 6 AM during the Night, while the lowest point, 43, was recorded at 3 PM during the Day between 25th Oct and 26th Oct 2025.
Day & Night AQI Trend : Sep - Oct 2025
Portage Park, Chicago, Illinois, United States
21°C13/31°C
23°C15/34°C
21°C16/26°C
21°C14/29°C
21°C17/27°C
21°C16/25°C
21°C14/30°C
24°C17/34°C
25°C18/33°C
24°C17/31°C
23°C17/31°C
16°C12/20°C
13°C9/17°C
12°C8/19°C
13°C7/21°C
14°C11/18°C
15°C10/21°C
16°C11/24°C
16°C14/19°C
14°C12/15°C
16°C12/21°C
18°C12/27°C
19°C16/24°C
12°C7/16°C
11°C4/18°C
9°C7/13°C
8°C6/10°C
6°C3/13°C
6°C0/12°C
8°C1/15°C
--°C/°C
48AQI
41AQI
46AQI
40AQI
2025 Days Vs Air Quality
Portage Park, Chicago, Illinois, United States
67%
143
32%
68
0.9%
2
Total number of days with different AQI categories in last 299 days in 2025 (66 days remaining)
Under WHO’s Safe Air Quality Limits: 67%
Health Risk Level:
Moderate
In 2025, 67% of 299 days were within WHO’s safe air quality limits, and 33% exceeded them. The risk of health issues is Moderate, particularly for individuals with respiratory or heart conditions.
Annual Air Quality Insights
Portage Park, Chicago, Illinois, United States
AQI levels in 2025
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
54AQI
47AQI
35AQI
32AQI
19AQI
21AQI
40AQI
28AQI
30AQI
25AQI
25AQI
27AQI
19AQI
38AQI
49AQI
47AQI
53AQI
47AQI
35AQI
20AQI
22AQI
38AQI
53AQI
42AQI
40AQI
21AQI
34AQI
30AQI
53AQI
26AQI
19AQI
31AQI
40AQI
34AQI
20AQI
31AQI
27AQI
16AQI
16AQI
21AQI
37AQI
41AQI
18AQI
22AQI
32AQI
23AQI
37AQI
35AQI
33AQI
46AQI
36AQI
22AQI
20AQI
18AQI
25AQI
18AQI
15AQI
19AQI
18AQI
14AQI
21AQI
26AQI
30AQI
40AQI
46AQI
40AQI
37AQI
43AQI
57AQI
57AQI
101AQI
83AQI
83AQI
78AQI
71AQI
62AQI
74AQI
80AQI
76AQI
63AQI
51AQI
56AQI
52AQI
39AQI
33AQI
44AQI
43AQI
47AQI
57AQI
43AQI
32AQI
49AQI
37AQI
23AQI
37AQI
34AQI
34AQI
55AQI
54AQI
57AQI
71AQI
52AQI
54AQI
66AQI
52AQI
44AQI
46AQI
29AQI
59AQI
72AQI
79AQI
50AQI
27AQI
29AQI
40AQI
29AQI
75AQI
81AQI
65AQI
56AQI
33AQI
39AQI
35AQI
46AQI
50AQI
49AQI
114AQI
93AQI
81AQI
88AQI
89AQI
88AQI
94AQI
70AQI
60AQI
58AQI
53AQI
48AQI
42AQI
52AQI
65AQI
74AQI
59AQI
36AQI
38AQI
26AQI
18AQI
18AQI
35AQI
36AQI
23AQI
19AQI
28AQI
38AQI
33AQI
25AQI
28AQI
35AQI
37AQI
41AQI
52AQI
44AQI
43AQI
21AQI
25AQI
34AQI
39AQI
54AQI
50AQI
51AQI
60AQI
60AQI
57AQI
56AQI
56AQI
60AQI
59AQI
60AQI
56AQI
42AQI
46AQI
22AQI
27AQI
42AQI
46AQI
50AQI
45AQI
49AQI
41AQI
46AQI
66AQI
69AQI
61AQI
49AQI
22AQI
34AQI
35AQI
54AQI
31AQI
38AQI
64AQI
60AQI
21AQI
34AQI
44AQI
72AQI
30AQI
26AQI
22AQI
17AQI
20AQI
31AQI
69AQI
37AQI
34AQI
27AQI
55AQI
53AQI
50AQI
46AQI
42AQI
No. of days
202544AQI
Highest AQI recorded in
June55AQI
Lowest AQI recorded in
May27AQI
Most & Least Polluted Years Over the Last 1 Years
Portage Park's annual 2025 AQI (44) shows an average percentage change of NaN% (improved AQI) compared to previous years: .