State air quality · 2025
Nebraska Air Quality Ranking
Across 11 monitored counties, the typical county in Nebraska posts a median AQI of 32 (Good) and 85.0% of monitored days were rated Good, from EPA AQS.
- 32
- Avg median AQI
- 85.0%
- Good-air days
- 11
- Counties monitored
- 88%
- Cleaner than US states
Nebraska's typical county median AQI is 32 (Good) across 11 monitored counties
According to the U.S. EPA Air Quality System, Nebraska monitors 11 counties with a day-weighted Good-day share of 85.0%. Cleanest: Cass County (95.9% Good). Most polluted: Douglas County (71.0%). These are annual summaries, not live AirNow readings.
Data source EPA Air Quality System (AQS)
- Cleaner than US states
- Nebraska's day-weighted Good-day share of 85.0% places it cleaner than 88% of US states.
- In-state spread
- Within Nebraska, Cass County leads at 95.9% Good days while Douglas County sits at 71.0% across 11 monitored counties.
- 2024→2025 release
- Nebraska's Good-day share moved +5.7 points vs the 2024 EPA annual release.
- Typical median AQI
- Typical median AQI: 32
Verify with AirNow → · EPA AQS →
EPA state monitoring brief
AQS state key NEBRASKA
Nebraska · 2025 EPA AQS · 11 counties · med AQI 32 · 85.0% Good · Cass→Douglas spread
- GOOD 32 Median AQI · Good
- SHARE 85.0% Good-day share
- COUNT 11 Counties monitored
- UNH 0 Unhealthy+ days
- RANK 88% Cleaner than states
- PM25 57.0% Main pollutant share
Good-day share peers
Nebraska's 85.0% Good-day share is cleaner than 88% of monitored US states; Cass and Douglas County bracket the in-state range. Open Cass County →
According to EPA AQS annual summaries on PlainAirData, Nebraska ranks #6 of 52 by day-weighted good-day share (85.0%) and #7 by mean county median AQI (31.6). Hawaii is #1 of 52 by day-weighted good-day share (93.8% of monitored days) at mean county median-AQI #4 (27.3) ≠ Alaska #1 lowest mean county median AQI (20.3) at good-day share #8 (84.4%).
Data updated August 2026
What changed, what drives it, and how thick is the sample
Three derived views WPR-style word count does not substitute for: release-over-release movement from county annual rows, the EPA main-pollutant day mix, and how many counties sit below the 100-day ranking floor.
Release change
85.0%
Good-day share in 2025, up 5.7 percentage points vs 2024. County-mean median AQI 32, within half a point of the 2024 county-mean median.
Pollutant mix
PM2.5
Main driver on 57.0% of pollutant-assigned days.
- PM2.5 57.0%
- Ozone 32.1%
- PM10 10.9%
Monitoring coverage
301
Average monitored days per county in the latest release. 1 of 11 counties sit below the 100-day floor used for cleanest/most-polluted claims.
Counties Monitored
11
Good Days %
85.0%
Avg Median AQI
32
Total Unhealthy Days
0
Best Air Quality
Cass County
Worst Air Quality
Douglas County
Where Nebraska sits nationally
COUNT-derived placement among 52 US states with at least 365 monitored days in the latest county release. Nebraska's day-weighted Good-day share is 85.0% - cleaner than 88% of that comparison set.
Nebraska Good-day share vs. every US state
Day-weighted share of monitored days in the Good band (AQI 0–50) - EPA AQS annual release
85.0% Cleaner than 88% higher than 88% of 52 US states
Each bar is a band; taller bars hold more US states. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source U.S. Environmental Protection Agency, Air Quality System (AQS) · 2025
Which counties in Nebraska have the cleanest and most polluted air?
Cleanest counties in Nebraska
Data Sources
Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by County dataset, 2020–2025. See our methodology for how AQI and median figures are computed.
Coverage: 11 counties in Nebraska with active monitoring stations. Unmonitored counties are not represented.
Source: U.S. EPA Air Quality System (AQS) Annual AQI by county summary files, aggregated to the state level · 2020–2025
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.
Informational only, not professional advice. Data from EPA AQS. See our disclaimer.