Zalla, Portugalete, Basque Country, Spain 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
Zalla, Portugalete, Basque Country, Spain
AQI Trends: Highest and Lowest
Same Day Analysis (18th October ):
On this day, AQI across the 5 years varied significantly: 2025 ranks 1st highest AQI at 77 of Moderate air quality on the same day.
Download 2024 Annual Data
World Air Quality Report

Day & Night AQI Trend: 18th Oct - 19th Oct 2025
Zalla, Portugalete, Basque Country, Spain
8 AM18th Oct 2025
7 PM
7 AM19th Oct 2025
AQI
AQI
77AQI
51AQI
In the last 24 hours,
Zalla's AQI reached its highest point of 77 at 8 AM during the Night, while the lowest point, undefined, was recorded at 7 AM during the Night between 18th Oct and 19th Oct 2025.
Day & Night AQI Trend : Sep - Oct 2025
Zalla, Portugalete, Basque Country, Spain
25°C19/36°C
21°C16/27°C
13°C11/15°C
12°C10/15°C
12°C10/14°C
13°C11/17°C
13°C9/18°C
14°C9/20°C
18°C11/27°C
18°C15/22°C
16°C13/19°C
16°C13/20°C
15°C11/20°C
17°C11/24°C
17°C15/21°C
16°C13/23°C
14°C11/16°C
15°C9/23°C
17°C12/26°C
16°C14/21°C
15°C14/18°C
15°C11/18°C
15°C9/23°C
18°C14/26°C
18°C14/25°C
17°C14/22°C
15°C12/21°C
15°C12/21°C
16°C12/23°C
--°C/°C
--°C/°C
50AQI
47AQI
50AQI
46AQI
2025 Days Vs Air Quality
Zalla, Portugalete, Basque Country, Spain
84%
244
16%
47
Total number of days with different AQI categories in last 291 days in 2025 (74 days remaining)
Under WHO’s Safe Air Quality Limits: 84%
Health Risk Level:
Low
In 2025, 84% of 291 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
Zalla, Portugalete, Basque Country, Spain
AQI levels in 2025
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
57AQI
40AQI
37AQI
29AQI
30AQI
32AQI
32AQI
29AQI
27AQI
31AQI
28AQI
31AQI
41AQI
46AQI
52AQI
59AQI
49AQI
55AQI
46AQI
39AQI
39AQI
31AQI
30AQI
31AQI
28AQI
29AQI
30AQI
31AQI
30AQI
30AQI
32AQI
35AQI
30AQI
33AQI
40AQI
44AQI
49AQI
40AQI
33AQI
40AQI
38AQI
43AQI
38AQI
33AQI
36AQI
38AQI
45AQI
47AQI
47AQI
57AQI
45AQI
41AQI
32AQI
33AQI
30AQI
29AQI
28AQI
38AQI
40AQI
39AQI
31AQI
36AQI
47AQI
48AQI
38AQI
31AQI
31AQI
30AQI
33AQI
26AQI
26AQI
23AQI
26AQI
30AQI
29AQI
29AQI
29AQI
20AQI
35AQI
24AQI
17AQI
20AQI
27AQI
30AQI
32AQI
37AQI
38AQI
24AQI
30AQI
37AQI
36AQI
43AQI
22AQI
34AQI
21AQI
26AQI
36AQI
44AQI
51AQI
47AQI
44AQI
38AQI
29AQI
29AQI
17AQI
17AQI
23AQI
24AQI
13AQI
18AQI
21AQI
18AQI
20AQI
26AQI
34AQI
18AQI
20AQI
31AQI
27AQI
25AQI
27AQI
37AQI
22AQI
28AQI
25AQI
24AQI
31AQI
39AQI
43AQI
34AQI
26AQI
29AQI
31AQI
34AQI
23AQI
32AQI
46AQI
45AQI
37AQI
31AQI
33AQI
22AQI
32AQI
32AQI
33AQI
23AQI
26AQI
30AQI
33AQI
49AQI
45AQI
20AQI
25AQI
37AQI
37AQI
27AQI
27AQI
28AQI
46AQI
57AQI
63AQI
57AQI
55AQI
59AQI
52AQI
38AQI
34AQI
42AQI
45AQI
54AQI
56AQI
58AQI
60AQI
53AQI
57AQI
53AQI
48AQI
47AQI
39AQI
37AQI
43AQI
53AQI
36AQI
33AQI
35AQI
39AQI
37AQI
30AQI
28AQI
30AQI
32AQI
38AQI
40AQI
46AQI
42AQI
37AQI
43AQI
48AQI
40AQI
34AQI
33AQI
32AQI
27AQI
25AQI
22AQI
30AQI
38AQI
42AQI
33AQI
29AQI
28AQI
25AQI
26AQI
25AQI
28AQI
34AQI
37AQI
31AQI
34AQI
36AQI
35AQI
40AQI
51AQI
57AQI
59AQI
59AQI
57AQI
55AQI
56AQI
54AQI
50AQI
39AQI
36AQI
33AQI
32AQI
34AQI
36AQI
42AQI
35AQI
32AQI
26AQI
21AQI
20AQI
22AQI
21AQI
25AQI
23AQI
25AQI
25AQI
29AQI
23AQI
22AQI
22AQI
25AQI
24AQI
24AQI
23AQI
22AQI
23AQI
27AQI
51AQI
52AQI
52AQI
32AQI
23AQI
22AQI
21AQI
27AQI
30AQI
35AQI
38AQI
31AQI
36AQI
41AQI
54AQI
59AQI
68AQI
48AQI
53AQI
53AQI
55AQI
51AQI
59AQI
55AQI
62AQI
60AQI
64AQI
77AQI
72AQI
75AQI
77AQI
36AQI
39AQI
31AQI
28AQI
32AQI
45AQI
35AQI
39AQI
29AQI
60AQI
No. of days
202536AQI
Highest AQI recorded in
October60AQI
Lowest AQI recorded in
April28AQI
202437AQI
Highest AQI recorded in
July43AQI
Lowest AQI recorded in
October28AQI
202337AQI
Highest AQI recorded in
June43AQI
Lowest AQI recorded in
January27AQI
202237AQI
Highest AQI recorded in
July60AQI
Lowest AQI recorded in
November24AQI
202135AQI
Highest AQI recorded in
March41AQI
Lowest AQI recorded in
November29AQI
202032AQI
Highest AQI recorded in
March45AQI
Lowest AQI recorded in
December25AQI
Most & Least Polluted Years Over the Last 6 Years
Zalla's annual 2025 AQI (36) shows an average percentage change of 2.7% (worsened AQI) compared to previous years: 2020 (32), 2021 (35), 2022 (37), 2023 (37), 2024 (37).