Air Quality Rankings for Michigan (2026)

Cities Tracked

State Avg AQI

Improving

Worsening

How Michigan Compares

Michigan has 28 cities tracked by EPA air-quality monitors, with a state-wide 5-year median AQI of 39 — 2 points cleaner than the national average of AQI 41. Keweenaw, Michigan ranks #1 with the cleanest air (AQI 13, Grade B), while Wayne, Michigan sits at the bottom (AQI 58, Grade C). The rankings below are computed from the EPA Air Quality System (AQS), which aggregates daily AQI readings from federally certified monitors into annual averages. Cities are sorted by 5-year median AQI (lowest = cleanest = #1). The 5-year window smooths out year-to-year volatility from weather and wildfire events.

Michigan is on an improving trajectory: 15 of 28 monitored cities show measurably cleaner air over the past decade, against just 7 that are getting worse. That mirrors the broader national pattern of falling particulate and ozone pollution as cleaner vehicles, cleaner power generation, and tighter industrial standards take effect.

The dominant pollutant across 15 of 28 Michigan cities is Ground-Level Ozone. Ground-level ozone forms when sunlight reacts with vehicle and industrial emissions. It is worst on hot, sunny, stagnant summer days and is the leading air quality concern across much of the Sun Belt and California. Other Michigan cities report Fine Particulate Matter (PM2.5) (12), Coarse Particulate Matter (PM10) (1) as their dominant concern.

The fastest-improving city in Michigan is Monroe, Michigan, with median AQI falling by 3.2 points per year. Steady improvement at that pace usually reflects fleet turnover (older diesels retiring), upwind power-plant retirements, or tighter regional emissions controls.

The city with the steepest decline is Missaukee, Michigan, where median AQI is rising by 0.9 points per year. Rapid deterioration in a single city usually points to either wildfire-smoke exposure (in the West) or a new local emissions source — a power plant, port, or freight corridor coming online.

Full Michigan Ranking

#	City	5yr Avg AQI	Current AQI	Worst Pollutant	Trend	Grade
1	Keweenaw, Michigan	13	16	PM2.5	Stable	B
2	Monroe, Michigan	21	25	PM10	Improving	A
3	Bay, Michigan	32	42	PM2.5	Improving	B
4	Tuscola, Michigan	33	34	Ozone	Stable	B
5	Wexford, Michigan	34	35	Ozone	Stable	B
6	Schoolcraft, Michigan	35	36	PM2.5	Stable	B
7	Manistee, Michigan	36	39	Ozone	Stable	B
8	Benzie, Michigan	36	38	Ozone	Improving	B
9	Clinton, Michigan	36	38	Ozone	Improving	B
10	Huron, Michigan	37	39	Ozone	Stable	B
11	Mason, Michigan	37	40	Ozone	Stable	B
12	Muskegon, Michigan	39	41	Ozone	Stable	B
13	Oakland, Michigan	39	41	Ozone	Improving	B
14	Berrien, Michigan	40	42	Ozone	Improving	B
15	Cass, Michigan	40	42	Ozone	Improving	B
16	Allegan, Michigan	40	42	Ozone	Improving	B
17	Ingham, Michigan	42	43	PM2.5	Improving	B
18	Genesee, Michigan	42	44	PM2.5	Improving	B
19	Chippewa, Michigan	43	43	PM2.5	Worsening	C
20	Missaukee, Michigan	43	48	Ozone	Worsening	C
21	Ottawa, Michigan	44	51	Ozone	Worsening	C
22	St. Clair, Michigan	44	49	PM2.5	Stable	C
23	Macomb, Michigan	44	51	Ozone	Worsening	C
24	Kent, Michigan	45	49	PM2.5	Stable	C
25	Lenawee, Michigan	45	50	PM2.5	Stable	C
26	Washtenaw, Michigan	46	52	PM2.5	Stable	C
27	Kalamazoo, Michigan	47	53	PM2.5	Worsening	C
28	Wayne, Michigan	58	61	PM2.5	Stable	C

Air quality data for Michigan is sourced from the EPA Air Quality System (AQS), which monitors outdoor air quality at thousands of stations nationwide.
, EPA Air Quality System

Frequently Asked Questions

Keweenaw, Michigan has the best air quality in Michigan with a 5-year average AQI of 13 and a Grade B (77/100). Its dominant pollutant is Fine Particulate Matter (PM2.5) and the long-run trend is stable.

Wayne, Michigan has the worst air quality in Michigan with a 5-year average AQI of 58 and a Grade C (50/100). Its dominant pollutant is Fine Particulate Matter (PM2.5).

Michigan has 28 cities with EPA air quality monitoring data, covering 2014-2023 of daily AQI measurements aggregated into annual averages.

Michigan's state-wide 5-year median AQI is 39, 2 points cleaner than the national average of AQI 41. Michigan is on an improving trajectory: 15 of 28 monitored cities show measurably cleaner air over the past decade, against just 7 that are getting worse. That mirrors the broader national pattern of falling particulate and ozone pollution as cleaner vehicles, cleaner power generation, and tighter industrial standards take effect.

Ground-Level Ozone is the dominant pollutant in 15 of 28 monitored Michigan cities. Ground-level ozone forms when sunlight reacts with vehicle and industrial emissions. It is worst on hot, sunny, stagnant summer days and is the leading air quality concern across much of the Sun Belt and California.

Michigan cities log an average of 3 days per year at "Unhealthy for Sensitive Groups" or worse, based on EPA monitor data over the last five years. Across all 28 Michigan cities tracked, that totals 475 unhealthy days over the period.

Sources: EPA Air Quality System (AQS)

Cities ranked by 5-year average AQI (lower is better). Grades factor in average AQI, trend direction, unhealthy days, and dominant pollutant.

Cleanest Cities Nationwide →All Air Quality in Michigan →Worst Air Quality Cities →Methodology →

The this entity category groups every U.S. air quality and pollution monitoring entity sharing this attribute. The list above is the data; the paragraphs below explain what the grouping means against the broader the EPA Air Quality System (AQS) distribution and how to read the relative rankings within the category.

For readers using this category as a starting point, the per-entity detail pages linked from the table above carry the underlying the EPA Air Quality System (AQS) data in full. The category-level view is the filter; the per-entity pages are the actual answer.

Source: EPA Outdoor Air Quality Data, 2026.