ImprovementUpdated April 2026
Cities With Improving Air Quality
10-year trends show cleaner air in these areas
Hawaii, Hawaii shows the strongest air quality improvement with a trend of -5.2 AQI points per year.
| # | Name | Metric | Change | Grade |
|---|---|---|---|---|
| 1 | Hawaii, Hawaii AQI 23, trend -5.2/yr | 23 | -5.2 | A |
| 2 | Carbon, Wyoming AQI 8, trend -4.8/yr | 8 | -4.8 | A |
| 3 | Uinta, Wyoming AQI 6, trend -4.5/yr | 6 | -4.5 | A |
| 4 | Rosebud, Montana AQI 3, trend -3.6/yr | 3 | -3.6 | A |
| 5 | St Croix, Virgin Islands AQI 29, trend -3.5/yr | 29 | -3.4 | A |
| 6 | Monroe, Michigan AQI 25, trend -3.2/yr | 25 | -3.2 | A |
| 7 | Matanuska-Susitna, Alaska AQI 14, trend -2.7/yr | 14 | -2.7 | A |
| 8 | Alexandria City, Virginia AQI 6, trend -2.5/yr | 6 | -2.5 | A |
| 9 | Napa, California AQI 41, trend -2.3/yr | 41 | -2.3 | B |
| 10 | Colleton, South Carolina AQI 26, trend -2.3/yr | 26 | -2.3 | A |
Hawaii, Hawaii shows the strongest air quality improvement with a trend of -5.2 AQI points per year.
Frequently Asked Questions
This report is auto-generated from real public data sources. Entities are ranked by their key metrics and the most notable changes and extremes are highlighted.
The underlying data is refreshed on a regular schedule. This report was generated from the most recent available data (last updated April 2026).
The primary metric varies by report type. It may represent a score, dollar amount, rate, or count depending on what the report is measuring.
Source: EPA Outdoor Air Quality Data, 2026.