EnviroNearby

Lincoln County, Missouri air quality history

Daily Air Quality Index summaries from EPA monitors in Lincoln, Missouri, 1999–2025.

85%
Good days in 2025
41
Median daily AQI, 2025
3
Days above 100 in 2025
247
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Lincoln, Missouri on 247 days. 210 of those days (85%) were in the Good range, and the median daily AQI was 41. That median is about the same as the typical monitored county in Missouri (median 41 across 19 counties), and about the same as the typical monitored U.S. county (40). The main pollutant was ozone on 247 days. Across the years with fuller monitoring, the share of Good days rose: an average of 71% in 2000–2006 versus 81% in 2023–2025.

EPA did not report an AQI for every day of 2025 here (247 of 365 days). Figures describe monitored days only; seasonal monitoring (for example, ozone measured only in warmer months) can make a county look cleaner or dirtier than a full-year record would.

Years with fewer than 120 monitored days (1999, 2001) 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%1999: Good 46 of 48 days1999: Moderate 2 of 48 days19992000: Good 120 of 121 days2000: Moderate 1 of 121 days2001: Good 116 of 116 days20012005: Good 112 of 214 days2005: Moderate 62 of 214 days2005: Unhealthy for Sensitive Groups 35 of 214 days2005: Unhealthy 5 of 214 days2006: Good 131 of 213 days2006: Moderate 63 of 213 days2006: Unhealthy for Sensitive Groups 17 of 213 days2006: Unhealthy 2 of 213 days20062007: Good 125 of 214 days2007: Moderate 65 of 214 days2007: Unhealthy for Sensitive Groups 17 of 214 days2007: Unhealthy 7 of 214 days2008: Good 156 of 213 days2008: Moderate 53 of 213 days2008: Unhealthy for Sensitive Groups 4 of 213 days20082009: Good 168 of 210 days2009: Moderate 41 of 210 days2009: Unhealthy for Sensitive Groups 1 of 210 days2010: Good 153 of 214 days2010: Moderate 49 of 214 days2010: Unhealthy for Sensitive Groups 11 of 214 days2010: Unhealthy 1 of 214 days20102011: Good 171 of 244 days2011: Moderate 61 of 244 days2011: Unhealthy for Sensitive Groups 12 of 244 days2012: Good 122 of 214 days2012: Moderate 69 of 214 days2012: Unhealthy for Sensitive Groups 19 of 214 days2012: Unhealthy 4 of 214 days20122013: Good 162 of 214 days2013: Moderate 48 of 214 days2013: Unhealthy for Sensitive Groups 4 of 214 days2014: Good 179 of 214 days2014: Moderate 35 of 214 days20142015: Good 188 of 214 days2015: Moderate 26 of 214 days2016: Good 182 of 214 days2016: Moderate 31 of 214 days2016: Unhealthy for Sensitive Groups 1 of 214 days20162017: Good 210 of 244 days2017: Moderate 33 of 244 days2017: Unhealthy for Sensitive Groups 1 of 244 days2018: Good 209 of 245 days2018: Moderate 33 of 245 days2018: Unhealthy for Sensitive Groups 3 of 245 days20182019: Good 223 of 245 days2019: Moderate 22 of 245 days2020: Good 228 of 245 days2020: Moderate 16 of 245 days2020: Unhealthy for Sensitive Groups 1 of 245 days20202021: Good 225 of 244 days2021: Moderate 19 of 244 days2022: Good 214 of 245 days2022: Moderate 30 of 245 days2022: Unhealthy for Sensitive Groups 1 of 245 days20222023: Good 177 of 245 days2023: Moderate 53 of 245 days2023: Unhealthy for Sensitive Groups 15 of 245 days2024: Good 225 of 266 days2024: Moderate 39 of 266 days2024: Unhealthy for Sensitive Groups 2 of 266 days20242025: Good 210 of 247 days2025: Moderate 34 of 247 days2025: Unhealthy for Sensitive Groups 3 of 247 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 year0501001501999: 90th percentile AQI 392000: 90th percentile AQI 272001: 90th percentile AQI 312005: 90th percentile AQI 1122006: 90th percentile AQI 1002007: 90th percentile AQI 1012008: 90th percentile AQI 742009: 90th percentile AQI 612010: 90th percentile AQI 842011: 90th percentile AQI 842012: 90th percentile AQI 1052013: 90th percentile AQI 712014: 90th percentile AQI 612015: 90th percentile AQI 542016: 90th percentile AQI 612017: 90th percentile AQI 612018: 90th percentile AQI 672019: 90th percentile AQI 502020: 90th percentile AQI 482021: 90th percentile AQI 492022: 90th percentile AQI 542023: 90th percentile AQI 802024: 90th percentile AQI 612025: 90th percentile AQI 581999: Median AQI 232000: Median AQI 142001: Median AQI 182005: Median AQI 502006: Median AQI 472007: Median AQI 482008: Median AQI 442009: Median AQI 412010: Median AQI 442011: Median AQI 442012: Median AQI 492013: Median AQI 442014: Median AQI 392015: Median AQI 392016: Median AQI 392017: Median AQI 422018: Median AQI 412019: Median AQI 402020: Median AQI 372021: Median AQI 392022: Median AQI 412023: Median AQI 442024: Median AQI 422025: Median AQI 411999200120062008201020122014201620182020202220242025
  • 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
Ozone247100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
20252472103430004158122Ozone
20242662253920004261143Ozone
202324517753150004480140Ozone
20222452143010004154112Ozone
2021244225190000394993Ozone
20202452281610003748108Ozone
20192452232200004050100Ozone
20182452093330004167143Ozone
20172442103310004261105Ozone
20162141823110003961101Ozone
2015214188260000395497Ozone
2014214179350000396197Ozone
20132141624840004471136Ozone
2012214122691940049105172Ozone
201124417161120004484140Ozone
201021415349111004484151Ozone
20092101684110004161101Ozone
20082131565340004474115Ozone
2007214125651770048101182Ozone
2006213131631720047100161Ozone
2005214112623550050112197Ozone
200111611600000183145PM10
200012112010000142753PM10
1999484620000233954PM10

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 Missouri with a similar median AQI in 2025

All monitored counties in Missouri

Source: U.S. EPA AirData, “Annual AQI by County” files for 1999–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem