EnviroNearby

DeSoto County, Mississippi air quality history

Daily Air Quality Index summaries from EPA monitors in DeSoto, Mississippi, 1980–2025.

69%
Good days in 2025
43
Median daily AQI, 2025
1
Days above 100 in 2025
365
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for DeSoto, Mississippi on 365 days. 252 of those days (69%) were in the Good range, and the median daily AQI was 43. That median is about the same as the typical monitored county in Mississippi (median 43 across 10 counties), and higher than the typical monitored U.S. county (40). The main pollutant was fine particles (PM2.5) on 245 days. Across the years with fuller monitoring, the share of Good days fell: an average of 69% in 1980–1982 versus 53% in 2023–2025.

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%1980: Good 221 of 335 days1980: Moderate 67 of 335 days1980: Unhealthy for Sensitive Groups 39 of 335 days1980: Unhealthy 8 of 335 days19801981: Good 226 of 311 days1981: Moderate 59 of 311 days1981: Unhealthy for Sensitive Groups 25 of 311 days1981: Unhealthy 1 of 311 days1982: Good 136 of 198 days1982: Moderate 50 of 198 days1982: Unhealthy for Sensitive Groups 11 of 198 days1982: Unhealthy 1 of 198 days1983: Good 150 of 231 days1983: Moderate 65 of 231 days1983: Unhealthy for Sensitive Groups 10 of 231 days1983: Unhealthy 5 of 231 days1983: Very Unhealthy 1 of 231 days1984: Good 198 of 270 days1984: Moderate 57 of 270 days1984: Unhealthy for Sensitive Groups 15 of 270 days1985: Good 191 of 251 days1985: Moderate 51 of 251 days1985: Unhealthy for Sensitive Groups 8 of 251 days1985: Unhealthy 1 of 251 days19851986: Good 171 of 262 days1986: Moderate 57 of 262 days1986: Unhealthy for Sensitive Groups 28 of 262 days1986: Unhealthy 5 of 262 days1986: Very Unhealthy 1 of 262 days1987: Good 161 of 272 days1987: Moderate 86 of 272 days1987: Unhealthy for Sensitive Groups 23 of 272 days1987: Unhealthy 2 of 272 days1988: Good 172 of 270 days1988: Moderate 60 of 270 days1988: Unhealthy for Sensitive Groups 30 of 270 days1988: Unhealthy 7 of 270 days1988: Very Unhealthy 1 of 270 days1989: Good 219 of 272 days1989: Moderate 45 of 272 days1989: Unhealthy for Sensitive Groups 7 of 272 days1989: Unhealthy 1 of 272 days1990: Good 151 of 269 days1990: Moderate 85 of 269 days1990: Unhealthy for Sensitive Groups 25 of 269 days1990: Unhealthy 8 of 269 days19901991: Good 200 of 274 days1991: Moderate 56 of 274 days1991: Unhealthy for Sensitive Groups 16 of 274 days1991: Unhealthy 2 of 274 days1992: Good 205 of 270 days1992: Moderate 53 of 270 days1992: Unhealthy for Sensitive Groups 11 of 270 days1992: Unhealthy 1 of 270 days1993: Good 210 of 271 days1993: Moderate 54 of 271 days1993: Unhealthy for Sensitive Groups 5 of 271 days1993: Unhealthy 2 of 271 days1994: Good 178 of 275 days1994: Moderate 74 of 275 days1994: Unhealthy for Sensitive Groups 20 of 275 days1994: Unhealthy 3 of 275 days1995: Good 145 of 262 days1995: Moderate 74 of 262 days1995: Unhealthy for Sensitive Groups 39 of 262 days1995: Unhealthy 4 of 262 days19951996: Good 196 of 275 days1996: Moderate 62 of 275 days1996: Unhealthy for Sensitive Groups 12 of 275 days1996: Unhealthy 4 of 275 days1996: Very Unhealthy 1 of 275 days1997: Good 120 of 214 days1997: Moderate 73 of 214 days1997: Unhealthy for Sensitive Groups 18 of 214 days1997: Unhealthy 2 of 214 days1997: Very Unhealthy 1 of 214 days1998: Good 147 of 267 days1998: Moderate 75 of 267 days1998: Unhealthy for Sensitive Groups 38 of 267 days1998: Unhealthy 7 of 267 days1999: Good 199 of 365 days1999: Moderate 120 of 365 days1999: Unhealthy for Sensitive Groups 36 of 365 days1999: Unhealthy 9 of 365 days1999: Very Unhealthy 1 of 365 days2000: Good 185 of 364 days2000: Moderate 129 of 364 days2000: Unhealthy for Sensitive Groups 43 of 364 days2000: Unhealthy 7 of 364 days20002001: Good 221 of 365 days2001: Moderate 127 of 365 days2001: Unhealthy for Sensitive Groups 17 of 365 days2002: Good 188 of 300 days2002: Moderate 91 of 300 days2002: Unhealthy for Sensitive Groups 15 of 300 days2002: Unhealthy 6 of 300 days2003: Good 141 of 270 days2003: Moderate 112 of 270 days2003: Unhealthy for Sensitive Groups 16 of 270 days2003: Unhealthy 1 of 270 days2004: Good 157 of 284 days2004: Moderate 113 of 284 days2004: Unhealthy for Sensitive Groups 12 of 284 days2004: Unhealthy 2 of 284 days2005: Good 132 of 282 days2005: Moderate 118 of 282 days2005: Unhealthy for Sensitive Groups 30 of 282 days2005: Unhealthy 2 of 282 days20052006: Good 148 of 278 days2006: Moderate 104 of 278 days2006: Unhealthy for Sensitive Groups 22 of 278 days2006: Unhealthy 4 of 278 days2007: Good 129 of 266 days2007: Moderate 111 of 266 days2007: Unhealthy for Sensitive Groups 24 of 266 days2007: Unhealthy 1 of 266 days2007: Very Unhealthy 1 of 266 days2008: Good 139 of 362 days2008: Moderate 212 of 362 days2008: Unhealthy for Sensitive Groups 11 of 362 days2009: Good 158 of 345 days2009: Moderate 182 of 345 days2009: Unhealthy for Sensitive Groups 5 of 345 days2010: Good 138 of 365 days2010: Moderate 219 of 365 days2010: Unhealthy for Sensitive Groups 8 of 365 days20102011: Good 147 of 338 days2011: Moderate 187 of 338 days2011: Unhealthy for Sensitive Groups 4 of 338 days2012: Good 160 of 363 days2012: Moderate 189 of 363 days2012: Unhealthy for Sensitive Groups 13 of 363 days2012: Unhealthy 1 of 363 days2013: Good 203 of 365 days2013: Moderate 161 of 365 days2013: Unhealthy for Sensitive Groups 1 of 365 days2014: Good 193 of 365 days2014: Moderate 171 of 365 days2014: Unhealthy for Sensitive Groups 1 of 365 days2015: Good 216 of 365 days2015: Moderate 149 of 365 days20152016: Good 186 of 325 days2016: Moderate 138 of 325 days2016: Unhealthy for Sensitive Groups 1 of 325 days2017: Good 221 of 365 days2017: Moderate 144 of 365 days2018: Good 199 of 365 days2018: Moderate 163 of 365 days2018: Unhealthy for Sensitive Groups 2 of 365 days2018: Unhealthy 1 of 365 days2019: Good 222 of 364 days2019: Moderate 141 of 364 days2019: Unhealthy for Sensitive Groups 1 of 364 days2020: Good 246 of 365 days2020: Moderate 119 of 365 days20202021: Good 228 of 364 days2021: Moderate 135 of 364 days2021: Unhealthy for Sensitive Groups 1 of 364 days2022: Good 211 of 365 days2022: Moderate 148 of 365 days2022: Unhealthy for Sensitive Groups 6 of 365 days2023: Good 122 of 360 days2023: Moderate 231 of 360 days2023: Unhealthy for Sensitive Groups 7 of 360 days2024: Good 208 of 366 days2024: Moderate 154 of 366 days2024: Unhealthy for Sensitive Groups 4 of 366 days2025: Good 252 of 365 days2025: Moderate 112 of 365 days2025: Unhealthy for Sensitive Groups 1 of 365 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 year0501001501980: 90th percentile AQI 1151981: 90th percentile AQI 901982: 90th percentile AQI 901983: 90th percentile AQI 871984: 90th percentile AQI 801985: 90th percentile AQI 801986: 90th percentile AQI 1121987: 90th percentile AQI 1001988: 90th percentile AQI 1151989: 90th percentile AQI 741990: 90th percentile AQI 1081991: 90th percentile AQI 931992: 90th percentile AQI 771993: 90th percentile AQI 711994: 90th percentile AQI 971995: 90th percentile AQI 1191996: 90th percentile AQI 871997: 90th percentile AQI 1001998: 90th percentile AQI 1191999: 90th percentile AQI 1052000: 90th percentile AQI 1052001: 90th percentile AQI 842002: 90th percentile AQI 872003: 90th percentile AQI 902004: 90th percentile AQI 822005: 90th percentile AQI 1082006: 90th percentile AQI 972007: 90th percentile AQI 1002008: 90th percentile AQI 772009: 90th percentile AQI 692010: 90th percentile AQI 742011: 90th percentile AQI 722012: 90th percentile AQI 742013: 90th percentile AQI 642014: 90th percentile AQI 642015: 90th percentile AQI 612016: 90th percentile AQI 632017: 90th percentile AQI 582018: 90th percentile AQI 632019: 90th percentile AQI 602020: 90th percentile AQI 582021: 90th percentile AQI 622022: 90th percentile AQI 632023: 90th percentile AQI 762024: 90th percentile AQI 672025: 90th percentile AQI 611980: Median AQI 391981: Median AQI 401982: Median AQI 441983: Median AQI 441984: Median AQI 421985: Median AQI 381986: Median AQI 441987: Median AQI 461988: Median AQI 441989: Median AQI 391990: Median AQI 471991: Median AQI 401992: Median AQI 391993: Median AQI 401994: Median AQI 441995: Median AQI 481996: Median AQI 411997: Median AQI 481998: Median AQI 491999: Median AQI 482000: Median AQI 492001: Median AQI 442002: Median AQI 432003: Median AQI 502004: Median AQI 472005: Median AQI 532006: Median AQI 492007: Median AQI 522008: Median AQI 542009: Median AQI 522010: Median AQI 542011: Median AQI 522012: Median AQI 522013: Median AQI 482014: Median AQI 492015: Median AQI 472016: Median AQI 472017: Median AQI 462018: Median AQI 492019: Median AQI 462020: Median AQI 442021: Median AQI 462022: Median AQI 482023: Median AQI 542024: Median AQI 472025: Median AQI 431980198519901995200020052010201520202025
  • 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)24567%
Ozone12033%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
202536525211210004361143PM2.5
202436620815440004767136PM2.5
202336012223170005476134PM2.5
202236521114860004863133PM2.5
202136422813510004662136PM2.5
202036524611900004458100PM2.5
201936422214110004660136PM2.5
201836519916321004963159PM2.5
201736522114400004658100PM2.5
201632518613810004763115PM2.5
20153652161490000476188PM2.5
201436519317110004964112PM2.5
201336520316110004864112PM2.5
2012363160189131005274151PM2.5
201133814718740005272129PM2.5
201036513821980005474147PM2.5
200934515818250005269143PM2.5
2008362139212110005477136PM2.5
20072661291112411052100203Ozone
2006278148104224004997179Ozone
20052821321183020053108172Ozone
2004284157113122004782169Ozone
2003270141112161005090151Ozone
200230018891156004387195Ozone
2001365221127170004484140Ozone
20003641851294370049105177Ozone
19993651991203691048105203Ozone
1998267147753870049119185Ozone
1997214120731821048100203Ozone
199627519662124104187215Ozone
1995262145743940048119179Ozone
199427517874203004497177Ozone
19932712105452004071154Ozone
199227020553111003977156Ozone
199127420056162004093161Ozone
1990269151852580047108182Ozone
19892722194571003974179Ozone
1988270172603071044115219Ozone
1987272161862320046100174Ozone
1986262171572851044112202Ozone
19852511915181003880151Ozone
198427019857150004280143Ozone
198323115065105104487207Ozone
198219813650111004490151Ozone
198131122659251004090156Ozone
1980335221673980039115195Ozone

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 Mississippi with a similar median AQI in 2025

All monitored counties in Mississippi

Source: U.S. EPA AirData, “Annual AQI by County” files for 1980–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem