Metro area air quality · 2024

Eau Claire, WI

Median AQI 38 (Good). 81.7% of monitored days rated Good across this metro's EPA monitoring network.

38
Median AQI
81.7%
Good-air days
0
Unhealthy days
70%
Cleaner than US metros

Aggregated from EPA Air Quality System (2024), 366 monitored days. EPA AQS → · NOAA →

Insights: Eau Claire, WI metro. Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 38 over 366 measured days in 2024, which corresponds to a Good band and a Good metro-wide health grade. The monitored-day split lands at 299 Good days (82%), 66 Moderate (18%), and 1 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 56 while the highest single-day reading hit 142 (USG). Metro residents averaged roughly 24.5 clean-air days per 30-day window across the reporting year.

Across the 2020–2024 trend window, good days shifted by +43 and the median AQI moved -4 points, which classifies the multi-year trajectory as improving. The metro avoided any Unhealthy-tier days entirely, an outcome that typically reflects favorable wind patterns, lower industrial density, or effective regional emission controls. Metros with comparable AQI profiles include Americus, GA (93.4% good, AQI 38); Beaver Dam, WI (81.2% good, AQI 38); Blacksburg-Christiansburg-Radford, VA (91.9% good, AQI 38).

Air Quality Summary

Median AQI

38

Good

Good Days

81.7%

299 of 366 days

Max AQI

142

USG

Health Grade

Good

90th pct: 56

AQI Day Breakdown (2024)

Distribution of 366 monitored days across EPA AQI categories.

Good

299

82%

Moderate

66

18%

USG

1

0%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Good

The Eau Claire, WI metro area's air quality is rated Good based on 81.7% good air days. No unhealthy air days were recorded in 2024.

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

How does the Eau Claire, WI metro compare?

How Eau Claire, WI compares

Good-day share better than US avg
Eau Claire, WI 81.7%
Americus, GA 93.4%
US average 70.2%
Median AQI better than US avg
Eau Claire, WI 38
Americus, GA 38
US average 41
Unhealthy days / yr better than US avg
Eau Claire, WI 0
Americus, GA 0
US average 1

5-Year Air Quality Trend

Air quality is improving in the Eau Claire, WI metro. Best year: 2024 (299 good days).

Year Good Moderate Unhealthy Median AQI
2020 256 110 0 42
2021 212 145 1 44
2022 268 97 0 41
2023 210 137 5 46
2024 299 66 0 38

Metros with Similar Air Quality

Metro areas across the US with a similar median AQI to Eau Claire, WI.

Americus, GA

AQI 38 · 93.4% good

38

Beaver Dam, WI

AQI 38 · 81.2% good

38

Blacksburg-Christiansburg-Radford, VA

AQI 38 · 91.9% good

38

Brainerd, MN

AQI 38 · 79.5% good

38

Dickinson, ND

AQI 38 · 82.8% good

38

Erie, PA

AQI 38 · 80.6% good

38

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Health Effects of Air Pollution

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Frequently Asked Questions

What is the air quality in the Eau Claire, WI metro area? ▼
The Eau Claire, WI metro area has a median Air Quality Index (AQI) of 38, rated "Good." 81.7% of monitored days (299 out of 366) had good air quality in 2024.
How many unhealthy air days does Eau Claire, WI have? ▼
In 2024, the Eau Claire, WI metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 142.
Is air quality in Eau Claire, WI getting better or worse? ▼
Air quality in the Eau Claire, WI metro is improving based on 5-year trends (2020-2024). Best year: 2024 with 299 good days. Worst year: 2023 with 210 good days.
What does AQI 38 mean for health? ▼
An AQI of 38 is "Good", air quality is satisfactory and poses little or no health risk. This is the best category on the EPA's AQI scale.
What is the 90th percentile AQI for Eau Claire, WI? ▼
The 90th percentile AQI for the Eau Claire, WI metro area is 56, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 142 (USG).
How does Eau Claire, WI compare to other metro areas? ▼
The Eau Claire, WI metro has 81.7% good air days. Similar metros: Americus, GA (93.4% good), Beaver Dam, WI (81.2% good), Blacksburg-Christiansburg-Radford, VA (91.9% good).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset, 2020–2024. The AQS collects ambient air monitoring data from state, local, and tribal monitoring agencies across the United States.

Metrics: Air Quality Index (AQI) is calculated using EPA-standard breakpoints for six criteria pollutants: PM2.5, PM10, Ozone, NO2, CO, and SO2. Median AQI, max AQI, and 90th percentile AQI are computed from daily measurements. Good days percentage reflects days with AQI 0–50.

Coverage: 501 metro areas (Core Based Statistical Areas). Only metros with active monitoring stations are included. Unmonitored areas are not represented.

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

Source: U.S. EPA, AirNow / AQS Air Quality Index readings and pollutant concentrations · 2025