Guelph, Ontario, Canada 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
Guelph, Ontario, Canada
AQI Trends: Highest and Lowest
Same Day Analysis (2nd August ):
On this day, AQI across the 5 years varied significantly: 2025 ranks 3rd highest AQI at 30 of Good air quality, showing improvement over 2024 and 2023 on the same day.
Download 2024 Annual Data
World Air Quality Report

Day & Night AQI Trend: 2nd Aug - 3rd Aug 2025
Guelph, Ontario, Canada
5 AM2nd Aug 2025
8 PM
4 AM3rd Aug 2025
80AQI
30AQI
101AQI
32AQI
In the last 24 hours,
Guelph's AQI reached its highest point of 101 at 12 AM during the Night, while the lowest point, undefined, was recorded at 4 AM during the Night between 2nd Aug and 3rd Aug 2025.
Day & Night AQI Trend : Jul - Aug 2025
Guelph, Ontario, Canada
19°C10/27°C
24°C15/32°C
26°C19/34°C
22°C19/24°C
21°C18/24°C
20°C14/25°C
22°C16/27°C
22°C16/29°C
26°C20/34°C
24°C20/29°C
24°C17/31°C
24°C15/33°C
24°C17/33°C
21°C16/24°C
17°C9/23°C
20°C11/29°C
21°C14/26°C
17°C11/22°C
17°C9/23°C
21°C12/31°C
25°C15/35°C
24°C21/28°C
22°C16/29°C
25°C19/32°C
24°C14/34°C
25°C19/33°C
23°C17/28°C
19°C14/24°C
17°C9/25°C
18°C9/26°C
--°C/°C
44AQI
44AQI
44AQI
44AQI
2025 Days Vs Air Quality
Guelph, Ontario, Canada
88%
189
12%
25
Total number of days with different AQI categories in last 215 days in 2025 (150 days remaining)
Under WHO’s Safe Air Quality Limits: 88%
Health Risk Level:
Low
In 2025, 88% of 215 days were within WHO’s safe air quality limits. The risk of health issues is Low, but the long-term effects, especially on vulnerable individuals, remain uncertain.
Annual Air Quality Insights
Guelph, Ontario, Canada
AQI levels in 2025
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
21AQI
21AQI
23AQI
28AQI
27AQI
23AQI
24AQI
28AQI
29AQI
45AQI
62AQI
45AQI
36AQI
26AQI
24AQI
49AQI
37AQI
30AQI
26AQI
25AQI
24AQI
30AQI
41AQI
26AQI
48AQI
31AQI
27AQI
29AQI
28AQI
25AQI
53AQI
27AQI
28AQI
55AQI
27AQI
25AQI
33AQI
28AQI
37AQI
32AQI
29AQI
40AQI
27AQI
26AQI
30AQI
33AQI
28AQI
28AQI
27AQI
25AQI
22AQI
28AQI
49AQI
59AQI
54AQI
61AQI
32AQI
38AQI
26AQI
30AQI
28AQI
31AQI
36AQI
37AQI
27AQI
32AQI
32AQI
30AQI
32AQI
31AQI
26AQI
29AQI
54AQI
56AQI
26AQI
15AQI
24AQI
31AQI
24AQI
17AQI
17AQI
19AQI
20AQI
18AQI
19AQI
27AQI
24AQI
30AQI
22AQI
21AQI
16AQI
17AQI
22AQI
17AQI
19AQI
16AQI
19AQI
14AQI
19AQI
34AQI
27AQI
23AQI
36AQI
27AQI
17AQI
13AQI
19AQI
33AQI
41AQI
16AQI
20AQI
14AQI
26AQI
37AQI
30AQI
27AQI
14AQI
22AQI
32AQI
17AQI
34AQI
28AQI
18AQI
16AQI
18AQI
19AQI
38AQI
18AQI
21AQI
27AQI
23AQI
27AQI
33AQI
21AQI
32AQI
29AQI
27AQI
19AQI
14AQI
14AQI
15AQI
12AQI
11AQI
13AQI
15AQI
18AQI
24AQI
23AQI
26AQI
33AQI
24AQI
18AQI
23AQI
39AQI
72AQI
54AQI
64AQI
64AQI
80AQI
69AQI
55AQI
61AQI
66AQI
44AQI
34AQI
37AQI
37AQI
39AQI
39AQI
30AQI
39AQI
48AQI
49AQI
53AQI
54AQI
43AQI
40AQI
37AQI
32AQI
35AQI
39AQI
38AQI
38AQI
47AQI
38AQI
43AQI
50AQI
47AQI
33AQI
39AQI
37AQI
46AQI
45AQI
45AQI
46AQI
58AQI
66AQI
46AQI
25AQI
31AQI
24AQI
42AQI
23AQI
22AQI
35AQI
35AQI
55AQI
42AQI
51AQI
43AQI
48AQI
91AQI
54AQI
30AQI
32AQI
34AQI
28AQI
23AQI
22AQI
46AQI
43AQI
42AQI
No. of days
202533AQI
Highest AQI recorded in
June46AQI
Lowest AQI recorded in
May22AQI
202432AQI
Highest AQI recorded in
January37AQI
Lowest AQI recorded in
November25AQI
202341AQI
Highest AQI recorded in
June68AQI
Lowest AQI recorded in
October31AQI
202235AQI
Highest AQI recorded in
November43AQI
Lowest AQI recorded in
August19AQI
202136AQI
Highest AQI recorded in
July40AQI
Lowest AQI recorded in
October30AQI
202033AQI
Highest AQI recorded in
November37AQI
Lowest AQI recorded in
October26AQI
Most & Least Polluted Years Over the Last 6 Years
Guelph's annual 2025 AQI (33) shows an average percentage change of -7.09% (improved AQI) compared to previous years: 2020 (33), 2021 (36), 2022 (35), 2023 (41), 2024 (32).