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AirHistory
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.

#NameMetricChangeGrade
1Hawaii, Hawaii
AQI 23 — trend -5.2/yr
23-5.2A
2Carbon, Wyoming
AQI 8 — trend -4.8/yr
8-4.8A
3Uinta, Wyoming
AQI 6 — trend -4.5/yr
6-4.5A
4Rosebud, Montana
AQI 3 — trend -3.6/yr
3-3.6A
5St Croix, Virgin Islands
AQI 29 — trend -3.5/yr
29-3.4A
6Monroe, Michigan
AQI 25 — trend -3.2/yr
25-3.2A
7Matanuska-Susitna, Alaska
AQI 14 — trend -2.7/yr
14-2.7A
8Alexandria City, Virginia
AQI 6 — trend -2.5/yr
6-2.5A
9Napa, California
AQI 41 — trend -2.3/yr
41-2.3B
10Colleton, South Carolina
AQI 26 — trend -2.3/yr
26-2.3A

Hawaii, Hawaii shows the strongest air quality improvement with a trend of -5.2 AQI points per year.

EPA Air Quality System (April 2026)

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.