EnviroNearby

Dyer County, Tennessee air quality history

Daily Air Quality Index summaries from EPA monitors in Dyer, Tennessee, 1995–2025.

77%
Good days in 2025
34
Median daily AQI, 2025
0
Days above 100 in 2025
359
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Dyer, Tennessee on 359 days. 276 of those days (77%) were in the Good range, and the median daily AQI was 34. That median is lower than the typical monitored county in Tennessee (median 39 across 23 counties), and lower than the typical monitored U.S. county (40). The main pollutant was fine particles (PM2.5) on 359 days. Across the years with fuller monitoring, the share of Good days rose: an average of 65% in 1995–2017 versus 78% in 2023–2025.

Years with fewer than 120 monitored days (2006, 2007, 2013, 2014, 2015, 2016…) are shown in the table but left out of comparisons and trend statements.

How the days broke down each year

Each bar is one year. The colored segments show the share of monitored days that fell in each AQI category.

Share of monitored days in each AQI category, by year0%25%50%75%100%1995: Good 128 of 200 days1995: Moderate 55 of 200 days1995: Unhealthy for Sensitive Groups 14 of 200 days1995: Unhealthy 3 of 200 days19951999: Good 5 of 28 days1999: Moderate 23 of 28 days2000: Good 24 of 106 days2000: Moderate 82 of 106 days20002001: Good 148 of 278 days2001: Moderate 124 of 278 days2001: Unhealthy for Sensitive Groups 6 of 278 days2002: Good 55 of 116 days2002: Moderate 60 of 116 days2002: Unhealthy for Sensitive Groups 1 of 116 days20022003: Good 41 of 105 days2003: Moderate 63 of 105 days2003: Unhealthy for Sensitive Groups 1 of 105 days2004: Good 52 of 111 days2004: Moderate 59 of 111 days20042005: Good 36 of 111 days2005: Moderate 73 of 111 days2005: Unhealthy for Sensitive Groups 2 of 111 days2006: Good 40 of 109 days2006: Moderate 66 of 109 days2006: Unhealthy for Sensitive Groups 2 of 109 days2006: Unhealthy 1 of 109 days20062007: Good 47 of 118 days2007: Moderate 69 of 118 days2007: Unhealthy for Sensitive Groups 2 of 118 days2013: Good 57 of 99 days2013: Moderate 42 of 99 days20132014: Good 62 of 109 days2014: Moderate 47 of 109 days2015: Good 71 of 111 days2015: Moderate 40 of 111 days20152016: Good 76 of 96 days2016: Moderate 20 of 96 days2017: Good 226 of 293 days2017: Moderate 67 of 293 days20172018: Good 257 of 356 days2018: Moderate 99 of 356 days2019: Good 275 of 360 days2019: Moderate 85 of 360 days20192020: Good 293 of 351 days2020: Moderate 57 of 351 days2020: Unhealthy for Sensitive Groups 1 of 351 days2021: Good 242 of 350 days2021: Moderate 107 of 350 days2021: Unhealthy for Sensitive Groups 1 of 350 days20212022: Good 258 of 356 days2022: Moderate 97 of 356 days2022: Unhealthy for Sensitive Groups 1 of 356 days2023: Good 267 of 360 days2023: Moderate 93 of 360 days20232024: Good 286 of 347 days2024: Moderate 61 of 347 days2025: Good 276 of 359 days2025: Moderate 83 of 359 days2025
  • Good
  • Moderate
  • Unhealthy for Sensitive Groups
  • Unhealthy
  • Very Unhealthy
  • Hazardous

Typical and high-end AQI over time

The median is the middle day of the year. The 90th percentile is the level that only the highest 10% of days exceeded.

Median and 90th-percentile daily AQI, by year0501001995: 90th percentile AQI 931999: 90th percentile AQI 782000: 90th percentile AQI 762001: 90th percentile AQI 842002: 90th percentile AQI 742003: 90th percentile AQI 722004: 90th percentile AQI 662005: 90th percentile AQI 792006: 90th percentile AQI 682007: 90th percentile AQI 772013: 90th percentile AQI 632014: 90th percentile AQI 642015: 90th percentile AQI 572016: 90th percentile AQI 532017: 90th percentile AQI 542018: 90th percentile AQI 562019: 90th percentile AQI 542020: 90th percentile AQI 532021: 90th percentile AQI 602022: 90th percentile AQI 562023: 90th percentile AQI 592024: 90th percentile AQI 532025: 90th percentile AQI 551995: Median AQI 461999: Median AQI 582000: Median AQI 582001: Median AQI 492002: Median AQI 522003: Median AQI 552004: Median AQI 522005: Median AQI 582006: Median AQI 532007: Median AQI 542013: Median AQI 482014: Median AQI 462015: Median AQI 422016: Median AQI 332017: Median AQI 392018: Median AQI 382019: Median AQI 352020: Median AQI 312021: Median AQI 392022: Median AQI 392023: Median AQI 392024: Median AQI 312025: Median AQI 34199520002002200420062013201520172019202120232025
  • Median daily AQI
  • 90th-percentile daily AQI

Main pollutant by day, 2025

On each monitored day, the AQI reflects whichever measured pollutant had the highest index. This counts how many days each pollutant set the AQI. A pollutant that was not measured here cannot appear.

PollutantDays as main pollutantShare of monitored days
Fine particles (PM2.5)359100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
2025359276830000345572PM2.5
2024347286610000315392PM2.5
2023360267930000395981PM2.5
20223562589710003956102PM2.5
202135024210710003960105PM2.5
20203512935710003153117PM2.5
2019360275850000355466PM2.5
2018356257990000385683PM2.5
2017293226670000395474PM2.5
20169676200000335361PM2.5
201511171400000425770PM2.5
201410962470000466482PM2.5
20139957420000486370PM2.5
2007118476920005477122PM2.5
2006109406621005368153PM2.5
2005111367320005879131PM2.5
200411152590000526692PM2.5
2003105416310005572106PM2.5
2002116556010005274101PM2.5
200127814812460004984133Ozone
200010624820000587694PM2.5
1999285230000587894PM2.5
199520012855143004693174Ozone

What this data can and can’t tell you

It is a county-level summary. EPA reports one AQI per day for the county, based on the monitors operating there. Air at a particular street, school or home can differ, especially near roads, industry or wildfire smoke.

It is not a health assessment. The AQI is EPA’s scale for communicating daily air quality. A county’s history can’t tell you what the health risk is for any particular person. For daily conditions and health guidance, see AirNow.

Rules change over time. EPA has revised AQI breakpoints, most recently for fine particles in 2024, so some year-to-year change can reflect the scale rather than the air.

Counties in Tennessee with a similar median AQI in 2025

All monitored counties in Tennessee

Source: U.S. EPA AirData, “Annual AQI by County” files for 1995–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem