Rossiter Pump House, Helena Valley West Central, Montana, United States 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
Rossiter Pump House, Helena Valley West Central, Montana, United States
AQI Trends: Highest and Lowest
Same Day Analysis (4th October ):
On this day, AQI across the 5 years varied significantly: 2025 ranks the most lowest AQI at 9 of Good air quality, showing improvement over 2024, 2023, 2022 and 2021 on the same day.
Download 2024 Annual Data
World Air Quality Report

Day & Night AQI Trend: 4th Oct - 5th Oct 2025
Rossiter Pump House, Helena Valley West Central, Montana, United States
7 AM4th Oct 2025
7 PM
6 AM5th Oct 2025
21AQI
7AQI
18AQI
8AQI
In the last 24 hours,
Rossiter Pump House's AQI reached its highest point of 21 at 2 PM during the Day, while the lowest point, undefined, was recorded at 6 AM during the Night between 4th Oct and 5th Oct 2025.
Day & Night AQI Trend : Sep - Oct 2025
Rossiter Pump House, Helena Valley West Central, Montana, United States
14°C5/23°C
18°C7/28°C
20°C12/29°C
19°C12/27°C
19°C10/28°C
18°C12/26°C
16°C7/24°C
16°C8/23°C
16°C9/23°C
16°C8/25°C
13°C7/19°C
14°C9/21°C
14°C7/23°C
16°C7/26°C
18°C9/25°C
20°C9/28°C
18°C9/28°C
15°C10/21°C
14°C4/25°C
17°C6/29°C
18°C6/28°C
17°C12/23°C
16°C6/26°C
16°C6/26°C
18°C9/29°C
17°C12/24°C
16°C9/23°C
14°C8/23°C
14°C10/20°C
11°C7/16°C
--°C/°C
42AQI
28AQI
32AQI
28AQI
2025 Days Vs Air Quality
Rossiter Pump House, Helena Valley West Central, Montana, United States
94%
261
6%
16
Total number of days with different AQI categories in last 278 days in 2025 (87 days remaining)
Under WHO’s Safe Air Quality Limits: 94%
Health Risk Level:
Very Low
In 2025, 94% of 278 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
Rossiter Pump House, Helena Valley West Central, Montana, United States
AQI levels in 2025
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
33AQI
31AQI
32AQI
29AQI
51AQI
48AQI
53AQI
37AQI
31AQI
31AQI
24AQI
22AQI
23AQI
27AQI
41AQI
49AQI
26AQI
28AQI
35AQI
35AQI
30AQI
25AQI
30AQI
37AQI
32AQI
50AQI
54AQI
60AQI
67AQI
61AQI
64AQI
31AQI
38AQI
30AQI
26AQI
34AQI
58AQI
41AQI
31AQI
24AQI
24AQI
38AQI
70AQI
55AQI
39AQI
24AQI
20AQI
18AQI
17AQI
30AQI
54AQI
19AQI
20AQI
17AQI
16AQI
14AQI
17AQI
21AQI
28AQI
31AQI
25AQI
26AQI
18AQI
17AQI
14AQI
16AQI
23AQI
19AQI
18AQI
17AQI
23AQI
29AQI
26AQI
25AQI
24AQI
26AQI
27AQI
23AQI
25AQI
23AQI
21AQI
19AQI
15AQI
24AQI
31AQI
31AQI
36AQI
30AQI
21AQI
25AQI
24AQI
29AQI
34AQI
28AQI
25AQI
22AQI
23AQI
21AQI
24AQI
33AQI
37AQI
36AQI
23AQI
27AQI
28AQI
30AQI
21AQI
23AQI
26AQI
25AQI
18AQI
19AQI
23AQI
24AQI
26AQI
26AQI
32AQI
28AQI
26AQI
22AQI
27AQI
25AQI
40AQI
31AQI
26AQI
23AQI
21AQI
26AQI
28AQI
30AQI
28AQI
29AQI
24AQI
24AQI
22AQI
22AQI
26AQI
26AQI
20AQI
21AQI
21AQI
22AQI
22AQI
23AQI
23AQI
27AQI
24AQI
23AQI
22AQI
21AQI
24AQI
32AQI
20AQI
26AQI
26AQI
26AQI
31AQI
32AQI
45AQI
46AQI
39AQI
40AQI
42AQI
44AQI
32AQI
37AQI
42AQI
36AQI
37AQI
34AQI
42AQI
24AQI
21AQI
26AQI
37AQI
39AQI
32AQI
31AQI
25AQI
30AQI
20AQI
27AQI
40AQI
32AQI
30AQI
34AQI
26AQI
26AQI
25AQI
24AQI
23AQI
32AQI
30AQI
31AQI
28AQI
23AQI
32AQI
35AQI
34AQI
33AQI
29AQI
26AQI
20AQI
26AQI
31AQI
33AQI
33AQI
24AQI
28AQI
25AQI
27AQI
32AQI
28AQI
28AQI
29AQI
34AQI
25AQI
29AQI
23AQI
17AQI
19AQI
30AQI
32AQI
26AQI
27AQI
37AQI
35AQI
41AQI
28AQI
25AQI
30AQI
46AQI
46AQI
36AQI
34AQI
37AQI
39AQI
41AQI
34AQI
32AQI
34AQI
32AQI
40AQI
40AQI
39AQI
57AQI
73AQI
69AQI
60AQI
65AQI
43AQI
46AQI
45AQI
35AQI
22AQI
20AQI
26AQI
20AQI
24AQI
33AQI
33AQI
34AQI
32AQI
32AQI
22AQI
24AQI
27AQI
31AQI
37AQI
45AQI
36AQI
35AQI
27AQI
12AQI
12AQI
10AQI
9AQI
39AQI
31AQI
23AQI
26AQI
25AQI
33AQI
29AQI
32AQI
38AQI
11AQI
No. of days
202530AQI
Highest AQI recorded in
January39AQI
Lowest AQI recorded in
October11AQI
202437AQI
Highest AQI recorded in
July57AQI
Lowest AQI recorded in
November19AQI
202334AQI
Highest AQI recorded in
August43AQI
Lowest AQI recorded in
February23AQI
202235AQI
Highest AQI recorded in
September59AQI
Lowest AQI recorded in
May23AQI
202137AQI
Highest AQI recorded in
July77AQI
Lowest AQI recorded in
April25AQI
202033AQI
Highest AQI recorded in
September53AQI
Lowest AQI recorded in
May20AQI
Most & Least Polluted Years Over the Last 6 Years
Rossiter Pump House's annual 2025 AQI (30) shows an average percentage change of -13.6% (improved AQI) compared to previous years: 2020 (33), 2021 (37), 2022 (35), 2023 (34), 2024 (37).