Harrow Stanmore, Stanmore, Harrow, United Kingdom 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
Harrow Stanmore, Stanmore, Harrow, United Kingdom
AQI Trends: Highest and Lowest
Same Day Analysis (16th September ):
On this day, AQI across the 4 years varied significantly: 2025 ranks 3rd highest AQI at 23 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: 16th Sep - 17th Sep 2025
Harrow Stanmore, Stanmore, Harrow, United Kingdom
6 AM16th Sep 2025
7 PM
5 AM17th Sep 2025
24AQI
20AQI
24AQI
18AQI
In the last 24 hours,
Harrow Stanmore's AQI reached its highest point of 24 at 9 AM during the Day, while the lowest point, 18, was recorded at 5 AM during the Night between 16th Sep and 17th Sep 2025.
Day & Night AQI Trend : Aug - Sep 2025
Harrow Stanmore, Stanmore, Harrow, United Kingdom
20°C16/25°C
19°C15/25°C
18°C15/22°C
17°C14/22°C
18°C12/24°C
18°C15/23°C
19°C17/24°C
21°C15/27°C
21°C17/26°C
18°C14/22°C
17°C13/21°C
16°C14/20°C
17°C13/21°C
17°C13/21°C
17°C14/21°C
15°C12/18°C
17°C14/19°C
16°C13/19°C
16°C12/22°C
19°C14/23°C
20°C16/25°C
17°C13/21°C
16°C12/21°C
16°C13/19°C
14°C11/18°C
14°C11/18°C
14°C12/18°C
14°C10/17°C
15°C14/19°C
15°C13/18°C
--°C/°C
28AQI
25AQI
27AQI
25AQI
2025 Days Vs Air Quality
Harrow Stanmore, Stanmore, Harrow, United Kingdom
74%
192
25%
66
0.3%
1
Total number of days with different AQI categories in last 260 days in 2025 (105 days remaining)
Under WHO’s Safe Air Quality Limits: 74%
Health Risk Level:
Low
In 2025, 74% of 260 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
Harrow Stanmore, Stanmore, Harrow, United Kingdom
AQI levels in 2025
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
28AQI
34AQI
44AQI
54AQI
31AQI
23AQI
25AQI
37AQI
51AQI
63AQI
89AQI
89AQI
56AQI
54AQI
56AQI
53AQI
58AQI
76AQI
69AQI
66AQI
69AQI
78AQI
57AQI
46AQI
38AQI
33AQI
27AQI
26AQI
28AQI
30AQI
35AQI
40AQI
57AQI
60AQI
39AQI
48AQI
51AQI
46AQI
65AQI
71AQI
80AQI
76AQI
70AQI
69AQI
66AQI
80AQI
70AQI
64AQI
74AQI
83AQI
45AQI
36AQI
43AQI
33AQI
27AQI
35AQI
28AQI
31AQI
50AQI
52AQI
59AQI
65AQI
66AQI
80AQI
79AQI
56AQI
63AQI
84AQI
126AQI
59AQI
48AQI
42AQI
52AQI
38AQI
42AQI
46AQI
53AQI
70AQI
65AQI
74AQI
55AQI
80AQI
88AQI
80AQI
58AQI
49AQI
33AQI
32AQI
34AQI
38AQI
38AQI
41AQI
56AQI
64AQI
40AQI
29AQI
32AQI
46AQI
40AQI
42AQI
59AQI
63AQI
49AQI
32AQI
45AQI
26AQI
31AQI
36AQI
43AQI
29AQI
41AQI
28AQI
23AQI
43AQI
44AQI
57AQI
66AQI
47AQI
54AQI
54AQI
59AQI
54AQI
50AQI
25AQI
22AQI
26AQI
35AQI
22AQI
31AQI
29AQI
33AQI
36AQI
38AQI
36AQI
35AQI
40AQI
36AQI
45AQI
37AQI
32AQI
38AQI
31AQI
30AQI
26AQI
19AQI
22AQI
20AQI
17AQI
21AQI
20AQI
22AQI
24AQI
21AQI
23AQI
22AQI
19AQI
16AQI
15AQI
20AQI
57AQI
39AQI
36AQI
46AQI
37AQI
36AQI
27AQI
26AQI
30AQI
32AQI
40AQI
47AQI
47AQI
50AQI
22AQI
22AQI
18AQI
18AQI
21AQI
17AQI
18AQI
23AQI
33AQI
32AQI
19AQI
19AQI
19AQI
17AQI
18AQI
21AQI
23AQI
21AQI
25AQI
30AQI
30AQI
33AQI
24AQI
22AQI
22AQI
23AQI
24AQI
22AQI
19AQI
18AQI
33AQI
45AQI
38AQI
37AQI
26AQI
28AQI
25AQI
29AQI
23AQI
22AQI
21AQI
26AQI
24AQI
25AQI
30AQI
30AQI
32AQI
25AQI
47AQI
52AQI
53AQI
59AQI
52AQI
41AQI
45AQI
36AQI
31AQI
32AQI
32AQI
29AQI
27AQI
26AQI
31AQI
32AQI
33AQI
30AQI
28AQI
23AQI
22AQI
24AQI
24AQI
22AQI
21AQI
21AQI
23AQI
25AQI
26AQI
24AQI
27AQI
24AQI
23AQI
20AQI
19AQI
20AQI
27AQI
23AQI
49AQI
55AQI
60AQI
43AQI
32AQI
29AQI
26AQI
33AQI
23AQI
No. of days
202540AQI
Highest AQI recorded in
March60AQI
Lowest AQI recorded in
September23AQI
202435AQI
Highest AQI recorded in
March67AQI
Lowest AQI recorded in
April4AQI
202339AQI
Highest AQI recorded in
February49AQI
Lowest AQI recorded in
August28AQI
202243AQI
Highest AQI recorded in
December51AQI
Lowest AQI recorded in
August22AQI
202143AQI
Highest AQI recorded in
September54AQI
Lowest AQI recorded in
April33AQI
202038AQI
Highest AQI recorded in
April55AQI
Lowest AQI recorded in
July25AQI
Most & Least Polluted Years Over the Last 6 Years
Harrow Stanmore's annual 2025 AQI (40) shows an average percentage change of 0.8% (worsened AQI) compared to previous years: 2020 (38), 2021 (43), 2022 (43), 2023 (39), 2024 (35).