Bad Air Days in Dyer County, Tennessee: under 1 a Year
under 1 bad air days a year
Rare: among the cleanest-air counties EPA monitors. Ranked 868 of 996 monitored counties, where 1 is worst.
What makes them bad: mostly particles: smoke and dust (100% particle days).
Which months to watch
- J
- F
- M
- A
- M
- J
- J
- A
- S
- O
- N
- D
Most bad days here fall in June and July. Averaged over 2016 to 2025.
What to buy, and what not to
- Bad air days are rare here. A standard furnace filter is enough; no purifier needed for outdoor air.
- On the odd bad day, check AirNow and keep windows shut.
The worst days on file
The worst recent year was 2021, with 1 bad day on 350 monitored days.
| Date | AQI | Main pollutant |
|---|---|---|
| 2020-06-27 | 117 | PM2.5 |
| 2021-07-22 | 105 | PM2.5 |
| 2022-06-14 | 102 | PM2.5 |
| 2021-07-21 | 93 | PM2.5 |
| 2021-07-23 | 92 | PM2.5 |
Most days, not the worst ones
Across 3,228 monitored days from 2016 to 2025, the air in Dyer County rated Good on 76% of them, more often than the 72% typical of monitored counties, and Moderate on 24%. The median day sat at AQI 36; one day in ten went above 56.
The pollutant setting the AQI on an ordinary day here:
- fine particles (PM2.5)100%3,228 days
Every recent year on file
| Year | Days monitored | Good | Moderate | Over 100 | Over 150 | Median AQI | Highest AQI |
|---|---|---|---|---|---|---|---|
| 2025* | 359 | 276 | 83 | 0 | 0 | 34 | 72 |
| 2024 | 347 | 286 | 61 | 0 | 0 | 31 | 92 |
| 2023 | 360 | 267 | 93 | 0 | 0 | 39 | 81 |
| 2022 | 356 | 258 | 97 | 1 | 0 | 39 | 102 |
| 2021 | 350 | 242 | 107 | 1 | 0 | 39 | 105 |
| 2020 | 351 | 293 | 57 | 1 | 0 | 31 | 117 |
| 2019 | 360 | 275 | 85 | 0 | 0 | 35 | 66 |
| 2018 | 356 | 257 | 99 | 0 | 0 | 38 | 83 |
| 2017 | 293 | 226 | 67 | 0 | 0 | 39 | 74 |
| 2016 | 96 | 76 | 20 | 0 | 0 | 33 | 61 |
| 2015 | 111 | 71 | 40 | 0 | 0 | 42 | 70 |
| 2014 | 109 | 62 | 47 | 0 | 0 | 46 | 82 |
| 2013 | 99 | 57 | 42 | 0 | 0 | 48 | 70 |
*2025 may be a partial year in EPA's file.
Elsewhere in Tennessee
- Shelby County6/yr
- Davidson County3/yr
- Blount County2/yr
- Sumner County2/yr
- Knox County2/yr
- Hamilton County2/yr
- Sevier County1/yr
- Loudon County1/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.