Washington(WA)
Air quality overview and monitoring data — 2025
535
Monitoring Sites
7,506
Active Monitors
38
Counties with Data
121
Cities Monitored
Loading county map...
County Air Quality
| County | Median AQI ▲ | 90th %ile | Max AQI | Good | Moderate | USG | Unhealthy |
|---|---|---|---|---|---|---|---|
| Klickitat | 14 | 53 | 55 | 16 | 3 | 0 | 0 |
| Pacific | 15 | 24 | 39 | 243 | 0 | 0 | 0 |
| Garfield | 18 | 38 | 80 | 233 | 10 | 0 | 0 |
| Lewis | 18 | 42 | 74 | 195 | 14 | 0 | 0 |
| Adams | 19 | 42 | 68 | 214 | 12 | 0 | 0 |
| Grays Harbor | 19 | 36 | 76 | 238 | 5 | 0 | 0 |
| Jefferson | 19 | 36 | 59 | 222 | 8 | 0 | 0 |
| Whitman | 20 | 41 | 97 | 228 | 15 | 0 | 0 |
| Cowlitz | 21 | 46 | 72 | 174 | 16 | 0 | 0 |
| Kitsap | 21 | 39 | 58 | 227 | 9 | 0 | 0 |
| Mason | 21 | 41 | 67 | 225 | 18 | 0 | 0 |
| Franklin | 22 | 44 | 61 | 223 | 15 | 0 | 0 |
| Kittitas | 22 | 54 | 81 | 206 | 37 | 0 | 0 |
| Skagit | 22 | 35 | 55 | 234 | 7 | 0 | 0 |
| Walla Walla | 25 | 54 | 80 | 209 | 34 | 0 | 0 |
| Clallam | 26 | 52 | 60 | 215 | 28 | 0 | 0 |
| Grant | 26 | 51 | 76 | 218 | 25 | 0 | 0 |
| Thurston | 26 | 44 | 52 | 158 | 3 | 0 | 0 |
| Chelan | 27 | 52 | 74 | 212 | 31 | 0 | 0 |
| Stevens | 27 | 57 | 119 | 197 | 45 | 1 | 0 |
| Whatcom | 30 | 43 | 58 | 229 | 8 | 0 | 0 |
| Clark | 31 | 51 | 80 | 217 | 26 | 0 | 0 |
| Okanogan | 31 | 58 | 86 | 178 | 60 | 0 | 0 |
| Yakima | 34 | 58 | 87 | 197 | 46 | 0 | 0 |
| Asotin | 35 | 65 | 151 | 177 | 61 | 1 | 1 |
| Benton | 35 | 51 | 68 | 216 | 27 | 0 | 0 |
| Columbia | 37 | 47 | 68 | 226 | 17 | 0 | 0 |
| Snohomish | 41 | 62 | 87 | 168 | 75 | 0 | 0 |
| Spokane | 42 | 58 | 71 | 172 | 71 | 0 | 0 |
| King | 43 | 61 | 90 | 164 | 79 | 0 | 0 |
| Pierce | 44 | 58 | 100 | 185 | 58 | 0 | 0 |
Pollutant Trends
Ozone
No data available
PM2.5
No data available
PM10
No data available
CO
No data available
NO2
No data available
SO2
No data available