Bad Air Days in Lake County, Oregon: 10 a Year
10 bad air days a year
Among the worst tenth of monitored US counties. Ranked 88 of 996 monitored counties, where 1 is worst.
What makes them bad: mostly particles: smoke and dust (100% particle days).
When the bad days come in Lake
- J
- F
- M
- A
- M
- J
- J
- A
- S
- O
- N
- D
Most bad days here fall in August and September and December. Averaged over 2016 to 2025.
What actually helps 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.
Better or worse than it was
In 2000 to 2009 this county averaged 9 bad days a year; in 2016 to 2025, 10. Not much has changed. The worst recent year was 2021, with 23 bad days on 365 monitored days.
| Date | AQI | Main pollutant |
|---|---|---|
| 2018-07-31 | 191 | PM2.5 |
| 2021-09-12 | 188 | PM2.5 |
| 2021-08-16 | 174 | PM2.5 |
| 2018-08-21 | 173 | PM2.5 |
| 2021-08-26 | 173 | PM2.5 |
Most days, not the worst ones
Across 3,634 monitored days from 2016 to 2025, the air in Lake County rated Good on 75% of them, close to the 72% typical of monitored counties, and Moderate on 23%. The median day sat at AQI 28; one day in ten went above 69.
The pollutant setting the AQI on an ordinary day here:
- fine particles (PM2.5)98%3,572 days
- coarse dust (PM10)2%62 days
Year by year
| Year | Days monitored | Good | Moderate | Over 100 | Over 150 | Median AQI | Highest AQI |
|---|---|---|---|---|---|---|---|
| 2025* | 364 | 293 | 70 | 1 | 0 | 26 | 105 |
| 2024 | 366 | 286 | 71 | 9 | 2 | 28 | 153 |
| 2023 | 365 | 266 | 98 | 1 | 0 | 28 | 134 |
| 2022 | 365 | 273 | 88 | 4 | 0 | 25 | 129 |
| 2021 | 365 | 240 | 102 | 23 | 6 | 28 | 188 |
| 2020 | 365 | 267 | 80 | 18 | 4 | 29 | 166 |
| 2019 | 363 | 288 | 74 | 1 | 0 | 25 | 106 |
| 2018 | 358 | 244 | 92 | 22 | 9 | 34 | 191 |
| 2017 | 363 | 258 | 87 | 18 | 4 | 29 | 166 |
| 2016 | 360 | 300 | 58 | 2 | 1 | 24 | 161 |
| 2015 | 365 | 270 | 92 | 3 | 0 | 28 | 125 |
| 2014 | 363 | 275 | 75 | 13 | 1 | 29 | 157 |
| 2013 | 363 | 211 | 114 | 38 | 20 | 43 | 198 |
| 2012 | 350 | 241 | 96 | 13 | 1 | 32 | 152 |
| 2011 | 364 | 264 | 80 | 20 | 5 | 28 | 165 |
| 2010 | 364 | 279 | 83 | 2 | 0 | 28 | 118 |
*2025 may be a partial year in EPA's file.
Elsewhere in Oregon
- Klamath County20/yr
- Josephine County17/yr
- Jackson County16/yr
- Lane County16/yr
- Deschutes County14/yr
- Harney County7/yr
- Crook County7/yr
- Clackamas County6/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, on the AQI 100 line in what counts as a bad air day.