Metro area air quality · 2025

Muskegon, MI

Median AQI 39 (Good). 83.5% of monitored days rated Good across this metro's EPA monitoring network.

39
Median AQI
83.5%
Good-air days
0
Unhealthy days
74%
Cleaner than US metros

Muskegon, MI posted a 2025 median AQI of 39 (Good) with 83.5% Good days

According to the U.S. EPA Air Quality System, the Muskegon, MI CBSA recorded a median AQI of 39 across 243 monitored days in 2025, with 83.5% rated Good and 0 unhealthy or worse. This is an annual metro comparison, not a live advisory.

Data source EPA Air Quality System (AQS)

Cleaner than US metros
The Muskegon, MI CBSA's 83.5% Good-day share places it cleaner than 74% of US metros in 2025.
Closest median-AQI peer
Bay City, MI (70.4% Good, median AQI 39) is the closest nationwide median-AQI peer to Muskegon, MI.
2020–2025 Good-day shift
Muskegon, MI's Good-day share moved -2.5 points from 2020 to 2025 (median AQI +2).
Median AQI
Median AQI: 39

Aggregated from EPA Air Quality System (2025), 243 monitored days. EPA AQS →

The verdict

Muskegon, MI sits in the upper Good-day tercile among EPA CBSA metros on this site (83.5% of 243 monitored days). On the EPA scale the metro runs good, cleaner than the median US metro, with a median AQI of 39 and 83.5% of 243 monitored days in the Good band.

39
median AQI · Good
83.5%
days rated Good
74%
cleaner than US metros
140
worst single reading

No day crossed into the Unhealthy tier across the metro's monitors in 2025.

Annual release change

What changed in the 2025 EPA annual release

2024 → 2025
  • Muskegon, MI metro's peak single-day AQI rose from 122 to 140 between the 2024 and 2025 EPA annual releases, a change of +18 points.

Compared against 239 monitored days in 2024 and 241 in 2025. These are arithmetic differences between two stored EPA annual summaries, not a cause claim or a live advisory.

National release changes Two-year CSV

Muskegon, MI sits in the upper Good-day tercile among EPA CBSA metros on this site (83.5% of 243 monitored days). Signature read: 83.5% Good-day share (high tercile vs CBSA corpus). Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 39 over 243 measured days in 2025 (Good / Good). The monitored-day split lands at 203 Good (84%), 38 Moderate (16%), and 2 Unhealthy-for-Sensitive-Groups (1%). The 90th-percentile AQI finished at 61; the highest single-day reading hit 140 (USG).

Across 2020–2025, Good-day share shifted -2.5 points and median AQI moved +2 (stable). No Unhealthy-tier days appear in this annual dataset. Metros with comparable AQI profiles include Bay City, MI (70.4% good, AQI 39); Brainerd, MN (74.3% good, AQI 39); Cambridge, MD (86.0% good, AQI 39).

Health effects of air pollution →

Air Quality Summary

Median AQI

39

Good

Good Days

83.5%

203 of 243 days

Max AQI

140

USG

Health Grade

Good

90th pct: 61

AQI Day Breakdown (2025)

Distribution of 243 monitored days across EPA AQI categories.

Good

203

84%

Moderate

38

16%

USG

2

1%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Good

The Muskegon, MI metro area's air quality is rated Good based on 83.5% good air days. No unhealthy air days were recorded in 2025.

Air quality is generally acceptable. Unusually sensitive people should monitor real-time conditions at AirNow.gov during high-pollution events.

How does the Muskegon, MI metro compare?

How Muskegon, MI compares

Good-day share better than typical
Muskegon, MI 83.5%
Bay City, MI 70.4%
Typical US metro 70.6%
Median AQI better than typical
Muskegon, MI 39
Bay City, MI 39
Typical US metro 41
Unhealthy days / yr better than typical
Muskegon, MI 0
Bay City, MI 0
Typical US metro 1

5-Year Air Quality Trend

Air quality is stable in the Muskegon, MI metro. Highest Good-day share: 2022 (88.7%, 211 of 238 monitored days).

Year Good Moderate Unhealthy Median AQI
2020 210 32 0 37
2021 209 48 0 40
2022 211 25 2 37
2023 187 44 0 41
2024 203 36 0 38
2025 203 38 0 39

Metros with a similar median AQI

CBSA peers nationwide whose annual median AQI sits near Muskegon, MI (39).

Bay City, MI

Median AQI 39 · 70.4% Good-day share

39

Brainerd, MN

Median AQI 39 · 74.3% Good-day share

39

Cambridge, MD

Median AQI 39 · 86.0% Good-day share

39

Charleston, WV

Median AQI 39 · 77.0% Good-day share

39

Dalton, GA

Median AQI 39 · 90.3% Good-day share

39

Harrisonburg, VA

Median AQI 39 · 80.0% Good-day share

39

Metros with similar unhealthy-day exposure

A second relationship type: metros whose unhealthy-or-worse day count is closest to Muskegon, MI's 0 (independent of median AQI).

Aberdeen, SD

0 unhealthy-or-worse days · median AQI 27

27

Aberdeen, WA

0 unhealthy-or-worse days · median AQI 22

22

Adrian, MI

0 unhealthy-or-worse days · median AQI 41

41

Akron, OH

0 unhealthy-or-worse days · median AQI 45

45

Albany, GA

0 unhealthy-or-worse days · median AQI 46

46

Albany, OR

0 unhealthy-or-worse days · median AQI 27

27

Frequently Asked Questions

How many unhealthy air days does Muskegon, MI have? ▼
In 2025, the Muskegon, MI metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 140.
What is the air quality in the Muskegon, MI metro area? ▼
The Muskegon, MI metro area has a median Air Quality Index (AQI) of 39, rated "Good." 83.5% of monitored days (203 out of 243) had good air quality in 2025.
Is air quality in Muskegon, MI getting better or worse? ▼
Air quality in the Muskegon, MI metro is stable across floor-qualifying years (2020-2025); years with fewer than 100 monitored days are excluded from that direction. Highest qualifying Good-day share: 2022 at 88.7% (211 of 238 days). Lowest qualifying Good-day share: 2023 at 81.0% (187 of 231 days).
What does AQI 39 mean for health? ▼
An AQI of 39 is "Good", air quality is satisfactory and poses little or no health risk. This is the best category on the EPA's AQI scale.
How does Muskegon, MI compare to other metro areas? ▼
The Muskegon, MI metro has 83.5% good air days. Similar metros: Bay City, MI (70.4% good), Brainerd, MN (74.3% good), Cambridge, MD (86.0% good).
What is the 90th percentile AQI for Muskegon, MI? ▼
The 90th percentile AQI for the Muskegon, MI metro area is 61, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 140 (USG).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for Muskegon, MI, 2025. See our methodology for how AQI, median, and coverage figures are computed.

Read our methodology , how this data is sourced, computed, and verified.

Source: U.S. EPA Air Quality System (AQS) Annual AQI by CBSA summary, Muskegon, MI · 2020–2025