Metro area air quality · 2025

Sheboygan, WI

Median AQI 41 (Good). 78.9% of monitored days rated Good across this metro's EPA monitoring network.

41
Median AQI
78.9%
Good-air days
1
Unhealthy days
65%
Cleaner than US metros

Sheboygan, WI posted a 2025 median AQI of 41 (Good) with 78.9% Good days

According to the U.S. EPA Air Quality System, the Sheboygan, WI CBSA recorded a median AQI of 41 across 199 monitored days in 2025, with 78.9% rated Good and 1 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 Sheboygan, WI CBSA's 78.9% Good-day share places it cleaner than 65% of US metros in 2025.
Closest median-AQI peer
Adrian, MI (69.3% Good, median AQI 41) is the closest nationwide median-AQI peer to Sheboygan, WI.
2020–2025 Good-day shift
Sheboygan, WI's Good-day share moved -2.4 points from 2020 to 2025 (median AQI +2).
Median AQI
Median AQI: 41

Aggregated from EPA Air Quality System (2025), 199 monitored days. EPA AQS →

The verdict

Sheboygan, WI's peak reading 156 is in the upper max-AQI tercile among CBSA metros here. On the EPA scale the metro runs good, cleaner than the median US metro, with a median AQI of 41 and 78.9% of 199 monitored days in the Good band.

41
median AQI · Good
78.9%
days rated Good
65%
cleaner than US metros
156
worst single reading

1 day reached Unhealthy or worse across the metro's monitors in 2025.

Annual release change

What changed in the 2025 EPA annual release

2024 → 2025
  • Sheboygan, WI metro's Good-day share fell from 83.8% to 81.3% between the 2024 and 2025 EPA annual releases, a change of -2.5 percentage points.
  • Sheboygan, WI metro's Unhealthy-category days fell from 2 to 1 between the 2024 and 2025 EPA annual releases, a change of -1 days.
  • Sheboygan, WI metro's peak single-day AQI fell from 166 to 156 between the 2024 and 2025 EPA annual releases, a change of -10 points.

Compared against 198 monitored days in 2024 and 193 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

Sheboygan, WI's peak reading 156 is in the upper max-AQI tercile among CBSA metros here. Signature read: peak AQI 156 (high tercile vs CBSA corpus). Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 41 over 199 measured days in 2025 (Good / Good). The monitored-day split lands at 157 Good (79%), 35 Moderate (18%), and 6 Unhealthy-for-Sensitive-Groups (3%). The 90th-percentile AQI finished at 77; the highest single-day reading hit 156 (Unhealthy).

Across 2020–2025, Good-day share shifted -2.4 points and median AQI moved +2 (stable). The annual record contains 1 day at Unhealthy or worse. Metros with comparable AQI profiles include Adrian, MI (69.3% good, AQI 41); Albany-Schenectady-Troy, NY (67.7% good, AQI 41); Ann Arbor, MI (69.3% good, AQI 41).

Health effects of air pollution →

Air Quality Summary

Median AQI

41

Good

Good Days

78.9%

157 of 199 days

Max AQI

156

Unhealthy

Health Grade

Good

90th pct: 77

AQI Day Breakdown (2025)

Distribution of 199 monitored days across EPA AQI categories.

Good

157

79%

Moderate

35

18%

USG

6

3%

Unhealthy

1

1%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Good

The Sheboygan, WI metro area's air quality is rated Good based on 78.9% good air days. There were 1 unhealthy days in 2025 when outdoor activity should be limited.

Air quality is acceptable most days, but 6 days reached "Unhealthy for Sensitive Groups" and peak AQI reached 156. Sensitive groups should monitor real-time conditions at AirNow.gov.

How does the Sheboygan, WI metro compare?

How Sheboygan, WI compares

Good-day share better than typical
Sheboygan, WI 78.9%
Adrian, MI 69.3%
Typical US metro 70.6%
Median AQI about typical
Sheboygan, WI 41
Adrian, MI 41
Typical US metro 41
Unhealthy days / yr about typical
Sheboygan, WI 1
Adrian, MI 0
Typical US metro 1

5-Year Air Quality Trend

Air quality is stable in the Sheboygan, WI metro. Highest Good-day share: 2022 (87.3%, 172 of 197 monitored days).

Year Good Moderate Unhealthy Median AQI
2020 170 31 2 39
2021 164 39 0 41
2022 172 24 1 40
2023 132 53 1 45
2024 166 30 2 40
2025 157 35 1 41

Metros with a similar median AQI

CBSA peers nationwide whose annual median AQI sits near Sheboygan, WI (41).

Adrian, MI

Median AQI 41 · 69.3% Good-day share

41

Albany-Schenectady-Troy, NY

Median AQI 41 · 67.7% Good-day share

41

Ann Arbor, MI

Median AQI 41 · 69.3% Good-day share

41

Bowling Green, KY

Median AQI 41 · 75.6% Good-day share

41

Brunswick, GA

Median AQI 41 · 74.3% Good-day share

41

Decatur, AL

Median AQI 41 · 78.4% Good-day share

41

Metros with similar unhealthy-day exposure

A second relationship type: metros whose unhealthy-or-worse day count is closest to Sheboygan, WI's 1 (independent of median AQI).

Bangor, ME

1 unhealthy-or-worse days · median AQI 33

33

Baraboo, WI

1 unhealthy-or-worse days · median AQI 35

35

Bartlesville, OK

1 unhealthy-or-worse days · median AQI 44

44

Beaumont-Port Arthur, TX

1 unhealthy-or-worse days · median AQI 52

52

Beaver Dam, WI

1 unhealthy-or-worse days · median AQI 40

40

Bellingham, WA

1 unhealthy-or-worse days · median AQI 31

31

Frequently Asked Questions

What is the 90th percentile AQI for Sheboygan, WI? ▼
The 90th percentile AQI for the Sheboygan, WI metro area is 77, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 156 (Unhealthy).
How many unhealthy air days does Sheboygan, WI have? ▼
In 2025, the Sheboygan, WI metro area recorded 1 unhealthy air days (1 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 156.
What is the air quality in the Sheboygan, WI metro area? ▼
The Sheboygan, WI metro area has a median Air Quality Index (AQI) of 41, rated "Good." 78.9% of monitored days (157 out of 199) had good air quality in 2025.
Is air quality in Sheboygan, WI getting better or worse? ▼
Air quality in the Sheboygan, WI 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 87.3% (172 of 197 days). Lowest qualifying Good-day share: 2023 at 71.0% (132 of 186 days).
What does AQI 41 mean for health? ▼
An AQI of 41 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 Sheboygan, WI compare to other metro areas? ▼
The Sheboygan, WI metro has 78.9% good air days. Similar metros: Adrian, MI (69.3% good), Albany-Schenectady-Troy, NY (67.7% good), Ann Arbor, MI (69.3% good).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for Sheboygan, WI, 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, Sheboygan, WI · 2020–2025