Metro area air quality · 2025
Baraboo, WI
Median AQI 35 (Good). 75.6% of monitored days rated Good across this metro's EPA monitoring network.
- 35
- Median AQI
- 75.6%
- Good-air days
- 1
- Unhealthy days
- 57%
- Cleaner than US metros
Baraboo, WI posted a 2025 median AQI of 35 (Good) with 75.6% Good days
According to the U.S. EPA Air Quality System, the Baraboo, WI CBSA recorded a median AQI of 35 across 365 monitored days in 2025, with 75.6% 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 Baraboo, WI CBSA's 75.6% Good-day share places it cleaner than 57% of US metros in 2025.
- Closest median-AQI peer
- Effingham, IL (95.5% Good, median AQI 35) is the closest nationwide median-AQI peer to Baraboo, WI.
- 2020–2025 Good-day shift
- Baraboo, WI's Good-day share moved +4.3 points from 2020 to 2025 (median AQI -6).
- Median AQI
- Median AQI: 35
Aggregated from EPA Air Quality System (2025), 365 monitored days. EPA AQS →
The verdict
The Baraboo, WI metro runs good on the EPA scale, cleaner than the median US metro, a median AQI of 35 with 75.6% of 365 monitored days in the Good band.
- 35
- median AQI · Good
- 75.6%
- days rated Good
- 57%
- cleaner than US metros
- 167
- 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
- Baraboo, WI metro's peak single-day AQI rose from 77 to 167 between the 2024 and 2025 EPA annual releases, a change of +90 points.
- Baraboo, WI metro's Good-day share fell from 85.2% to 76.7% between the 2024 and 2025 EPA annual releases, a change of -8.6 percentage points.
- Baraboo, WI metro's Unhealthy-category days rose from 0 to 1 between the 2024 and 2025 EPA annual releases, a change of +1 days.
Insights: Baraboo, WI metro. Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 35 over 365 measured days in 2025, which corresponds to a Good band and a Good metro-wide health grade. The monitored-day split lands at 276 Good days (76%), 83 Moderate (23%), and 5 Unhealthy-for-Sensitive-Groups (1%). The 90th-percentile AQI finished at 58 while the highest single-day reading hit 167 (Unhealthy). Metro residents averaged roughly 22.7 clean-air days per 30-day window across the reporting year.
Across the 2020–2025 trend window, the share of monitored days rated Good shifted by +4.3 points and the median AQI moved -6 points, which classifies the multi-year trajectory as improving. The annual record contains 1 day at Unhealthy or worse. On that day, the EPA recommends that sensitive groups limit prolonged outdoor exertion. Metros with comparable AQI profiles include Effingham, IL (95.5% good, AQI 35); Ithaca, NY (93.2% good, AQI 35); Kinston, NC (97.5% good, AQI 35).
Air Quality Summary
Median AQI
35
Good
Good Days
75.6%
276 of 365 days
Max AQI
167
Unhealthy
Health Grade
Good
90th pct: 58
AQI Day Breakdown (2025)
Distribution of 365 monitored days across EPA AQI categories.
Good
276
76%
Moderate
83
23%
USG
5
1%
Unhealthy
1
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Health Impact Assessment
The Baraboo, WI metro area's air quality is rated Good based on 75.6% good air days. There were 1 unhealthy days in 2025 when outdoor activity should be limited.
Air quality is acceptable most days, but 5 days reached "Unhealthy for Sensitive Groups" and peak AQI reached 167. Sensitive groups should monitor real-time conditions at AirNow.gov.
How does the Baraboo, WI metro compare?
How Baraboo, WI compares
5-Year Air Quality Trend
Air quality is improving in the Baraboo, WI metro. Highest Good-day share: 2024 (85.2%, 312 of 366 monitored days).
| Year | Good | Moderate | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|
| 2020 | 264 | 101 | 0 | 41 | 112 |
| 2021 | 236 | 129 | 0 | 44 | 96 |
| 2022 | 265 | 95 | 0 | 41 | 79 |
| 2023 | 218 | 123 | 4 | 44 | 271 |
| 2024 | 312 | 54 | 0 | 37 | 77 |
| 2025 | 276 | 83 | 1 | 35 | 167 |
Metros with a similar median AQI
CBSA peers nationwide whose annual median AQI sits near Baraboo, WI (35).
Effingham, IL
Median AQI 35 · 95.5% Good-day share
Ithaca, NY
Median AQI 35 · 93.2% Good-day share
Kinston, NC
Median AQI 35 · 97.5% Good-day share
Meridian, MS
Median AQI 35 · 94.6% Good-day share
Morehead City, NC
Median AQI 35 · 96.2% Good-day share
Salem, OR
Median AQI 35 · 80.0% Good-day share
Metros with similar unhealthy-day exposure
A second relationship type: metros whose unhealthy-or-worse day count is closest to Baraboo, WI's 1 (independent of median AQI).
Ann Arbor, MI
1 unhealthy-or-worse days · median AQI 41
Bangor, ME
1 unhealthy-or-worse days · median AQI 33
Bartlesville, OK
1 unhealthy-or-worse days · median AQI 44
Beaumont-Port Arthur, TX
1 unhealthy-or-worse days · median AQI 52
Beaver Dam, WI
1 unhealthy-or-worse days · median AQI 40
Bellingham, WA
1 unhealthy-or-worse days · median AQI 31
More Air Quality Data
Explore EPA air quality rankings and guides across U.S. metros and counties.
Cleanest Metro Areas
U.S. metros ranked by their share of Good air-quality days.
Worst Air Quality
Counties and metros with the most unhealthy air days.
All Metro Areas
Annual AQI by CBSA for every monitored U.S. metro area.
Best and Worst City Air
What drives urban air quality and how metro areas compare.
Air Quality Guides
Frequently Asked Questions
What is the air quality in the Baraboo, WI metro area? ▼
How many unhealthy air days does Baraboo, WI have? ▼
Is air quality in Baraboo, WI getting better or worse? ▼
What does AQI 35 mean for health? ▼
What is the 90th percentile AQI for Baraboo, WI? ▼
How does Baraboo, WI compare to other metro areas? ▼
Data Sources
Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset, 2020–2025. 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 files (metro-level) · 2020–2025
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Every figure on PlainAirData is rendered directly from EPA AQS air-quality monitoring data, no number is typed in by an editor. This page draws directly on EPA AQS air-quality monitoring data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.