Bad Air Days in Inyo County, California: 29 a Year
29 bad air days a year
Among the worst tenth of monitored US counties. Ranked 16 of 996 monitored counties, where 1 is worst.
What makes them bad: mostly particles: smoke and dust (80% particle days).
Which months to watch
- J
- F
- M
- A
- M
- J
- J
- A
- S
- O
- N
- D
Most bad days here fall in September and October and August. Averaged over 2016 to 2025.
Is a purifier worth it here?
- Particles (wildfire smoke, dust) cause enough bad days here to matter. A HEPA purifier sized to your bedroom removes them; run it with windows shut on bad days.
- Upgrade the furnace or AC filter to MERV 13 so the whole house is filtered, not just one room.
- With this many bad days, whole-home filtration is worth an HVAC contractor quote.
- Ozone drives many bad days here. Purifiers and filters do not remove ozone, so do not buy one for that. Ozone peaks on hot afternoons: exercise outside in the morning.
Better or worse than it was
In 2000 to 2009 this county averaged 58 bad days a year; in 2016 to 2025, 29. The air has improved. The worst recent year was 2020, with 55 bad days on 366 monitored days.
| Date | AQI | Main pollutant |
|---|---|---|
| 2017-04-07 | 2234 | PM10 |
| 2022-04-11 | 1551 | PM10 |
| 2024-03-14 | 1322 | PM10 |
| 2017-03-31 | 1187 | PM10 |
| 2017-03-30 | 957 | PM10 |
Most days, not the worst ones
Across 3,653 monitored days from 2016 to 2025, the air in Inyo County rated Good on 43% of them, less often than the 72% typical of monitored counties, and Moderate on 49%. The median day sat at AQI 54; one day in ten went above 97.
The pollutant setting the AQI on an ordinary day here:
- ozone64%2,343 days
- fine particles (PM2.5)26%967 days
- coarse dust (PM10)9%343 days
Inyo County by year
| Year | Days monitored | Good | Moderate | Over 100 | Over 150 | Median AQI | Highest AQI |
|---|---|---|---|---|---|---|---|
| 2025* | 365 | 136 | 216 | 13 | 4 | 55 | 411 |
| 2024 | 366 | 90 | 246 | 30 | 13 | 61 | 1322 |
| 2023 | 365 | 106 | 236 | 23 | 10 | 61 | 786 |
| 2022 | 365 | 117 | 217 | 31 | 13 | 58 | 1551 |
| 2021 | 365 | 100 | 223 | 42 | 18 | 61 | 558 |
| 2020 | 366 | 158 | 153 | 55 | 32 | 57 | 705 |
| 2019 | 365 | 226 | 127 | 12 | 6 | 47 | 653 |
| 2018 | 365 | 192 | 136 | 37 | 11 | 49 | 638 |
| 2017 | 365 | 195 | 145 | 25 | 9 | 49 | 2234 |
| 2016 | 366 | 238 | 105 | 23 | 8 | 45 | 418 |
| 2015 | 365 | 191 | 153 | 21 | 9 | 49 | 1482 |
| 2014 | 365 | 222 | 128 | 15 | 9 | 48 | 957 |
| 2013 | 365 | 219 | 125 | 21 | 11 | 47 | 417 |
| 2012 | 366 | 198 | 139 | 29 | 14 | 49 | 4182 |
| 2011 | 365 | 159 | 160 | 46 | 13 | 54 | 14703 |
| 2010 | 365 | 236 | 98 | 31 | 18 | 44 | 4909 |
*2025 may be a partial year in EPA's file.
Elsewhere in California
- San Bernardino County138/yr
- Riverside County132/yr
- Kern County109/yr
- Tulare County107/yr
- Los Angeles County106/yr
- Fresno County81/yr
- Kings County49/yr
- Imperial County40/yr
How this is counted
A bad air day is a day the county's daily AQI from EPA AirData went above 100, the level where EPA tells children, older adults and people with asthma or heart disease to cut back outdoors. Monitors do not run every day, so yearly counts are scaled to 365 days. This is the record, not today's air: for that, check AirNow. More on the method in how the county numbers are made.