Daily Air Quality Index summaries from EPA monitors in Manistee, Michigan, 1990–2025.
80%
Good days in 2025
33
Median daily AQI, 2025
9
Days above 100 in 2025
361
Days with an AQI in 2025 (of 365)
In 2025, EPA reported a daily Air Quality Index (AQI) for Manistee, Michigan on 361 days. 287 of those days (80%) were in the Good range, and the median daily AQI was 33. That median is lower than the typical monitored county in Michigan (median 39 across 26 counties), and lower than the typical monitored U.S. county (40). The main pollutant was fine particles (PM2.5) on 208 days. Across the years with fuller monitoring, the share of Good days fell: an average of 85% in 1990–1992 versus 80% in 2023–2025.
How the days broke down each year
Each bar is one year. The colored segments show the share of monitored days that fell in each AQI category.
Good
Moderate
Unhealthy for Sensitive Groups
Unhealthy
Very Unhealthy
Hazardous
Typical and high-end AQI over time
The median is the middle day of the year. The 90th percentile is the level that only the highest 10% of days exceeded.
Median daily AQI
90th-percentile daily AQI
Main pollutant by day, 2025
On each monitored day, the AQI reflects whichever measured pollutant had the highest index. This counts how many days each pollutant set the AQI. A pollutant that was not measured here cannot appear.
Pollutant
Days as main pollutant
Share of monitored days
Fine particles (PM2.5)
208
58%
Ozone
153
42%
Year-by-year data
Annual AQI summary by year
Year
Days with AQI
Good
Moderate
Unhealthy for Sensitive Groups
Unhealthy
Very Unhealthy
Hazardous
Median AQI
90th pct.
Max AQI
Main pollutant
2025
361
287
65
6
3
0
0
33
65
167
PM2.5
2024
154
125
28
1
0
0
0
33
58
105
Ozone
2023
309
244
57
7
1
0
0
39
69
161
Ozone
2022
267
235
29
2
1
0
0
35
52
156
Ozone
2021
269
218
48
3
0
0
0
38
58
115
Ozone
2020
139
127
12
0
0
0
0
30
50
80
PM2.5
2019
269
243
25
1
0
0
0
36
50
101
Ozone
2018
265
222
42
1
0
0
0
34
57
112
Ozone
2017
280
236
43
1
0
0
0
37
54
108
Ozone
2016
241
208
31
2
0
0
0
34
55
133
Ozone
2015
242
202
38
2
0
0
0
36
59
119
Ozone
2014
241
201
38
2
0
0
0
37
58
101
Ozone
2013
234
179
53
2
0
0
0
40
67
124
Ozone
2012
241
164
55
22
0
0
0
40
97
147
Ozone
2011
236
185
46
4
1
0
0
38
61
164
Ozone
2010
236
186
47
3
0
0
0
40
67
122
Ozone
2009
237
196
40
1
0
0
0
38
58
136
Ozone
2008
241
184
55
2
0
0
0
41
65
133
Ozone
2007
239
161
61
15
2
0
0
42
90
161
Ozone
2006
187
144
36
5
2
0
0
34
71
200
Ozone
2000
234
205
22
6
0
1
0
37
58
205
Ozone
1999
361
296
42
13
10
0
0
36
84
190
Ozone
1998
352
279
52
17
4
0
0
36
74
187
Ozone
1997
360
311
39
9
1
0
0
35
64
159
Ozone
1996
207
172
28
4
2
1
0
31
71
203
Ozone
1995
268
213
38
11
6
0
0
38
87
174
Ozone
1994
360
303
47
8
2
0
0
35
71
169
Ozone
1993
361
328
26
6
1
0
0
33
49
151
Ozone
1992
361
313
32
16
0
0
0
32
58
150
Ozone
1991
358
293
35
24
6
0
0
34
87
177
Ozone
1990
359
310
31
16
2
0
0
34
64
164
Ozone
What this data can and can’t tell you
It is a county-level summary. EPA reports one AQI per day for the county, based on the monitors operating there. Air at a particular street, school or home can differ, especially near roads, industry or wildfire smoke.
It is not a health assessment. The AQI is EPA’s scale for communicating daily air quality. A county’s history can’t tell you what the health risk is for any particular person. For daily conditions and health guidance, see AirNow.
Rules change over time. EPA has revised AQI breakpoints, most recently for fine particles in 2024, so some year-to-year change can reflect the scale rather than the air.
Counties in Michigan with a similar median AQI in 2025
