Harjula, Lohja, Uusimaa, Finland 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
Harjula, Lohja, Uusimaa, Finland
AQI Trends: Highest and Lowest
Same Day Analysis (20th September ):
On this day, AQI across the 5 years varied significantly: 2025 ranks 1st highest AQI at 16 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
Harjula, Lohja, Uusimaa, Finland
6 AM20th Sep 2025
8 PM
5 AM21st Sep 2025
19AQI
12AQI
38AQI
15AQI
In the last 24 hours,
Harjula's AQI reached its highest point of 38 at 5 AM during the Night, while the lowest point, 12, was recorded at 10 AM during the Day between 20th Sep and 21st Sep 2025.
Day & Night AQI Trend : Aug - Sep 2025
Harjula, Lohja, Uusimaa, Finland
11°C6/16°C
12°C8/17°C
11°C7/16°C
11°C7/17°C
11°C6/16°C
12°C8/17°C
14°C8/19°C
13°C11/15°C
15°C14/16°C
15°C14/17°C
15°C12/19°C
16°C11/20°C
16°C13/20°C
16°C12/22°C
17°C13/23°C
19°C14/24°C
19°C15/25°C
19°C15/25°C
18°C14/23°C
18°C14/22°C
18°C15/23°C
14°C13/15°C
15°C11/18°C
14°C11/17°C
13°C12/15°C
14°C12/16°C
13°C11/15°C
13°C10/17°C
13°C10/16°C
14°C10/16°C
--°C/°C
22AQI
20AQI
22AQI
20AQI
2025 Days Vs Air Quality
Harjula, Lohja, Uusimaa, Finland
95%
250
5%
13
Total number of days with different AQI categories in last 264 days in 2025 (101 days remaining)
Under WHO’s Safe Air Quality Limits: 95%
Health Risk Level:
Very Low
In 2025, 95% 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
Harjula, Lohja, Uusimaa, Finland
AQI levels in 2025
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
23AQI
20AQI
21AQI
22AQI
20AQI
26AQI
23AQI
30AQI
19AQI
27AQI
19AQI
20AQI
21AQI
21AQI
21AQI
20AQI
21AQI
23AQI
21AQI
21AQI
22AQI
23AQI
25AQI
22AQI
29AQI
23AQI
23AQI
32AQI
31AQI
20AQI
20AQI
19AQI
19AQI
28AQI
40AQI
32AQI
24AQI
32AQI
35AQI
42AQI
49AQI
26AQI
21AQI
20AQI
25AQI
27AQI
24AQI
21AQI
21AQI
25AQI
29AQI
31AQI
56AQI
62AQI
74AQI
88AQI
65AQI
36AQI
34AQI
22AQI
22AQI
21AQI
24AQI
22AQI
23AQI
32AQI
52AQI
37AQI
44AQI
32AQI
34AQI
23AQI
25AQI
26AQI
14AQI
16AQI
15AQI
25AQI
28AQI
31AQI
35AQI
31AQI
47AQI
62AQI
49AQI
31AQI
43AQI
56AQI
60AQI
54AQI
41AQI
32AQI
28AQI
26AQI
17AQI
17AQI
18AQI
18AQI
19AQI
16AQI
18AQI
20AQI
18AQI
34AQI
32AQI
29AQI
27AQI
27AQI
38AQI
15AQI
14AQI
16AQI
17AQI
13AQI
16AQI
14AQI
16AQI
19AQI
15AQI
14AQI
15AQI
16AQI
13AQI
13AQI
13AQI
14AQI
13AQI
13AQI
14AQI
16AQI
17AQI
19AQI
24AQI
18AQI
15AQI
17AQI
15AQI
19AQI
20AQI
18AQI
14AQI
24AQI
22AQI
14AQI
15AQI
18AQI
19AQI
20AQI
28AQI
24AQI
17AQI
13AQI
19AQI
20AQI
32AQI
28AQI
22AQI
18AQI
15AQI
18AQI
18AQI
31AQI
40AQI
20AQI
19AQI
23AQI
24AQI
33AQI
25AQI
18AQI
16AQI
16AQI
14AQI
18AQI
23AQI
17AQI
14AQI
18AQI
18AQI
17AQI
15AQI
17AQI
17AQI
17AQI
15AQI
17AQI
17AQI
23AQI
19AQI
17AQI
18AQI
22AQI
35AQI
38AQI
39AQI
50AQI
44AQI
37AQI
29AQI
31AQI
33AQI
35AQI
38AQI
50AQI
52AQI
56AQI
55AQI
42AQI
38AQI
37AQI
40AQI
46AQI
38AQI
25AQI
26AQI
31AQI
24AQI
22AQI
18AQI
20AQI
26AQI
22AQI
19AQI
16AQI
14AQI
21AQI
22AQI
14AQI
12AQI
12AQI
13AQI
11AQI
13AQI
12AQI
12AQI
13AQI
11AQI
12AQI
13AQI
14AQI
16AQI
17AQI
16AQI
15AQI
17AQI
18AQI
19AQI
21AQI
28AQI
44AQI
43AQI
36AQI
38AQI
34AQI
24AQI
21AQI
20AQI
24AQI
19AQI
16AQI
15AQI
15AQI
16AQI
23AQI
36AQI
33AQI
21AQI
17AQI
21AQI
33AQI
18AQI
24AQI
No. of days
202525AQI
Highest AQI recorded in
February36AQI
Lowest AQI recorded in
May17AQI
202421AQI
Highest AQI recorded in
March29AQI
Lowest AQI recorded in
November16AQI
202320AQI
Highest AQI recorded in
April26AQI
Lowest AQI recorded in
October12AQI
202220AQI
Highest AQI recorded in
March30AQI
Lowest AQI recorded in
September12AQI
202124AQI
Highest AQI recorded in
June30AQI
Lowest AQI recorded in
April14AQI
Most & Least Polluted Years Over the Last 5 Years
Harjula's annual 2025 AQI (25) shows an average percentage change of 20.2% (worsened AQI) compared to previous years: 2021 (24), 2022 (20), 2023 (20), 2024 (21).