Great Synthe, Grande Synthe, Hauts De France, France 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
Great Synthe, Grande Synthe, Hauts De France, France
AQI Trends: Highest and Lowest
Same Day Analysis (8th October ):
On this day, AQI across the 5 years varied significantly: 2025 ranks 2nd highest AQI at 56 of Moderate air quality, showing improvement over 2021 on the same day.
Download 2024 Annual Data
World Air Quality Report

Day & Night AQI Trend: 8th Oct - 9th Oct 2025
Great Synthe, Grande Synthe, Hauts De France, France
7 AM8th Oct 2025
7 PM
6 AM9th Oct 2025
67AQI
49AQI
65AQI
32AQI
In the last 24 hours,
Great Synthe's AQI reached its highest point of 67 at 3 PM during the Day, while the lowest point, undefined, was recorded at 6 AM during the Night between 8th Oct and 9th Oct 2025.
Day & Night AQI Trend : Sep - Oct 2025
Great Synthe, Grande Synthe, Hauts De France, France
17°C15/19°C
16°C14/21°C
16°C15/18°C
15°C14/18°C
15°C13/17°C
16°C13/19°C
17°C15/18°C
16°C15/18°C
16°C14/20°C
19°C17/21°C
20°C16/26°C
19°C16/21°C
14°C13/15°C
14°C14/16°C
14°C13/16°C
15°C13/16°C
14°C13/15°C
13°C11/16°C
14°C11/17°C
14°C11/18°C
15°C14/16°C
15°C14/16°C
14°C12/17°C
15°C12/19°C
14°C13/15°C
15°C13/15°C
14°C13/16°C
15°C13/17°C
16°C14/18°C
14°C13/16°C
--°C/°C
37AQI
33AQI
35AQI
33AQI
2025 Days Vs Air Quality
Great Synthe, Grande Synthe, Hauts De France, France
71%
199
25%
70
4%
12
Total number of days with different AQI categories in last 282 days in 2025 (83 days remaining)
Under WHO’s Safe Air Quality Limits: 71%
Health Risk Level:
Low
In 2025, 71% of 282 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
Great Synthe, Grande Synthe, Hauts De France, France
AQI levels in 2025
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
34AQI
27AQI
30AQI
52AQI
37AQI
26AQI
26AQI
40AQI
31AQI
65AQI
77AQI
53AQI
90AQI
90AQI
85AQI
75AQI
80AQI
78AQI
82AQI
104AQI
90AQI
102AQI
58AQI
41AQI
38AQI
32AQI
31AQI
32AQI
30AQI
31AQI
39AQI
65AQI
83AQI
102AQI
75AQI
65AQI
59AQI
56AQI
69AQI
49AQI
122AQI
123AQI
78AQI
80AQI
108AQI
103AQI
79AQI
74AQI
85AQI
91AQI
78AQI
57AQI
53AQI
48AQI
31AQI
48AQI
38AQI
29AQI
39AQI
37AQI
77AQI
117AQI
130AQI
130AQI
97AQI
57AQI
71AQI
92AQI
143AQI
83AQI
40AQI
30AQI
31AQI
39AQI
43AQI
40AQI
46AQI
82AQI
80AQI
62AQI
46AQI
43AQI
93AQI
109AQI
50AQI
66AQI
54AQI
35AQI
41AQI
28AQI
45AQI
51AQI
55AQI
71AQI
64AQI
38AQI
36AQI
54AQI
32AQI
26AQI
58AQI
71AQI
44AQI
33AQI
54AQI
21AQI
41AQI
39AQI
46AQI
42AQI
65AQI
46AQI
22AQI
59AQI
42AQI
63AQI
48AQI
52AQI
62AQI
61AQI
78AQI
73AQI
49AQI
23AQI
27AQI
22AQI
23AQI
34AQI
33AQI
38AQI
32AQI
40AQI
52AQI
56AQI
49AQI
41AQI
40AQI
47AQI
44AQI
36AQI
52AQI
37AQI
32AQI
29AQI
28AQI
33AQI
24AQI
29AQI
33AQI
21AQI
34AQI
36AQI
29AQI
26AQI
21AQI
21AQI
24AQI
20AQI
22AQI
50AQI
50AQI
44AQI
50AQI
58AQI
50AQI
35AQI
38AQI
38AQI
40AQI
44AQI
43AQI
38AQI
35AQI
29AQI
33AQI
27AQI
29AQI
30AQI
18AQI
23AQI
35AQI
50AQI
50AQI
29AQI
25AQI
25AQI
18AQI
21AQI
29AQI
30AQI
31AQI
28AQI
23AQI
30AQI
50AQI
35AQI
35AQI
36AQI
41AQI
42AQI
24AQI
20AQI
21AQI
26AQI
39AQI
31AQI
46AQI
29AQI
32AQI
39AQI
34AQI
26AQI
22AQI
21AQI
23AQI
24AQI
23AQI
26AQI
28AQI
33AQI
35AQI
42AQI
49AQI
50AQI
58AQI
57AQI
38AQI
47AQI
33AQI
26AQI
27AQI
29AQI
25AQI
20AQI
22AQI
22AQI
27AQI
32AQI
30AQI
28AQI
22AQI
22AQI
21AQI
23AQI
19AQI
18AQI
20AQI
19AQI
20AQI
22AQI
23AQI
21AQI
23AQI
21AQI
20AQI
17AQI
19AQI
29AQI
29AQI
24AQI
18AQI
20AQI
35AQI
23AQI
23AQI
18AQI
17AQI
22AQI
40AQI
57AQI
59AQI
55AQI
30AQI
48AQI
84AQI
45AQI
50AQI
56AQI
47AQI
52AQI
56AQI
55AQI
71AQI
67AQI
48AQI
38AQI
35AQI
32AQI
31AQI
26AQI
55AQI
No. of days
202545AQI
Highest AQI recorded in
February71AQI
Lowest AQI recorded in
September26AQI
202440AQI
Highest AQI recorded in
November50AQI
Lowest AQI recorded in
July31AQI
202342AQI
Highest AQI recorded in
February61AQI
Lowest AQI recorded in
August31AQI
202244AQI
Highest AQI recorded in
March75AQI
Lowest AQI recorded in
August25AQI
202141AQI
Highest AQI recorded in
June70AQI
Lowest AQI recorded in
January26AQI
202030AQI
Highest AQI recorded in
November41AQI
Lowest AQI recorded in
July20AQI
Most & Least Polluted Years Over the Last 6 Years
Great Synthe's annual 2025 AQI (45) shows an average percentage change of 16.3% (worsened AQI) compared to previous years: 2020 (30), 2021 (41), 2022 (44), 2023 (42), 2024 (40).