EnviroNearby

Madison County, Virginia air quality history

Daily Air Quality Index summaries from EPA monitors in Madison, Virginia, 1983–2025.

86%
Good days in 2025
40
Median daily AQI, 2025
0
Days above 100 in 2025
330
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Madison, Virginia on 330 days. 283 of those days (86%) were in the Good range, and the median daily AQI was 40. That median is higher than the typical monitored county in Virginia (median 37 across 25 counties), and about the same as the typical monitored U.S. county (40). The main pollutant was ozone on 269 days. Across the years with fuller monitoring, the share of Good days rose: an average of 68% in 1985–1987 versus 86% in 2023–2025.

Years with fewer than 120 monitored days (1983, 1984) 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%1983: Good 9 of 17 days1983: Moderate 7 of 17 days1983: Unhealthy for Sensitive Groups 1 of 17 days19831984: Good 27 of 39 days1984: Moderate 8 of 39 days1984: Unhealthy for Sensitive Groups 4 of 39 days1985: Good 119 of 163 days1985: Moderate 35 of 163 days1985: Unhealthy for Sensitive Groups 8 of 163 days1985: Unhealthy 1 of 163 days1986: Good 232 of 321 days1986: Moderate 63 of 321 days1986: Unhealthy for Sensitive Groups 25 of 321 days1986: Unhealthy 1 of 321 days1987: Good 214 of 364 days1987: Moderate 94 of 364 days1987: Unhealthy for Sensitive Groups 48 of 364 days1987: Unhealthy 7 of 364 days1987: Very Unhealthy 1 of 364 days1988: Good 194 of 337 days1988: Moderate 97 of 337 days1988: Unhealthy for Sensitive Groups 23 of 337 days1988: Unhealthy 21 of 337 days1988: Very Unhealthy 2 of 337 days19881989: Good 241 of 343 days1989: Moderate 95 of 343 days1989: Unhealthy for Sensitive Groups 7 of 343 days1990: Good 201 of 339 days1990: Moderate 108 of 339 days1990: Unhealthy for Sensitive Groups 26 of 339 days1990: Unhealthy 4 of 339 days1991: Good 172 of 319 days1991: Moderate 112 of 319 days1991: Unhealthy for Sensitive Groups 32 of 319 days1991: Unhealthy 3 of 319 days1992: Good 221 of 355 days1992: Moderate 114 of 355 days1992: Unhealthy for Sensitive Groups 19 of 355 days1992: Unhealthy 1 of 355 days1993: Good 201 of 345 days1993: Moderate 118 of 345 days1993: Unhealthy for Sensitive Groups 24 of 345 days1993: Unhealthy 2 of 345 days19931994: Good 207 of 348 days1994: Moderate 115 of 348 days1994: Unhealthy for Sensitive Groups 25 of 348 days1994: Unhealthy 1 of 348 days1995: Good 194 of 341 days1995: Moderate 96 of 341 days1995: Unhealthy for Sensitive Groups 44 of 341 days1995: Unhealthy 7 of 341 days1996: Good 207 of 346 days1996: Moderate 107 of 346 days1996: Unhealthy for Sensitive Groups 31 of 346 days1996: Unhealthy 1 of 346 days1997: Good 202 of 350 days1997: Moderate 121 of 350 days1997: Unhealthy for Sensitive Groups 23 of 350 days1997: Unhealthy 4 of 350 days1998: Good 173 of 341 days1998: Moderate 92 of 341 days1998: Unhealthy for Sensitive Groups 57 of 341 days1998: Unhealthy 15 of 341 days1998: Very Unhealthy 4 of 341 days19981999: Good 171 of 346 days1999: Moderate 108 of 346 days1999: Unhealthy for Sensitive Groups 53 of 346 days1999: Unhealthy 14 of 346 days2000: Good 216 of 357 days2000: Moderate 113 of 357 days2000: Unhealthy for Sensitive Groups 27 of 357 days2000: Unhealthy 1 of 357 days2001: Good 183 of 336 days2001: Moderate 117 of 336 days2001: Unhealthy for Sensitive Groups 29 of 336 days2001: Unhealthy 7 of 336 days2002: Good 221 of 356 days2002: Moderate 97 of 356 days2002: Unhealthy for Sensitive Groups 32 of 356 days2002: Unhealthy 6 of 356 days2003: Good 209 of 341 days2003: Moderate 118 of 341 days2003: Unhealthy for Sensitive Groups 9 of 341 days2003: Unhealthy 5 of 341 days20032004: Good 246 of 349 days2004: Moderate 93 of 349 days2004: Unhealthy for Sensitive Groups 9 of 349 days2004: Unhealthy 1 of 349 days2005: Good 220 of 339 days2005: Moderate 106 of 339 days2005: Unhealthy for Sensitive Groups 13 of 339 days2006: Good 203 of 333 days2006: Moderate 115 of 333 days2006: Unhealthy for Sensitive Groups 15 of 333 days2007: Good 213 of 354 days2007: Moderate 132 of 354 days2007: Unhealthy for Sensitive Groups 9 of 354 days2008: Good 257 of 361 days2008: Moderate 97 of 361 days2008: Unhealthy for Sensitive Groups 7 of 361 days20082009: Good 305 of 361 days2009: Moderate 54 of 361 days2009: Unhealthy for Sensitive Groups 2 of 361 days2010: Good 211 of 318 days2010: Moderate 99 of 318 days2010: Unhealthy for Sensitive Groups 8 of 318 days2011: Good 213 of 360 days2011: Moderate 142 of 360 days2011: Unhealthy for Sensitive Groups 5 of 360 days2012: Good 249 of 352 days2012: Moderate 97 of 352 days2012: Unhealthy for Sensitive Groups 6 of 352 days2013: Good 298 of 357 days2013: Moderate 59 of 357 days20132014: Good 291 of 360 days2014: Moderate 69 of 360 days2015: Good 280 of 361 days2015: Moderate 81 of 361 days2016: Good 302 of 361 days2016: Moderate 58 of 361 days2016: Unhealthy for Sensitive Groups 1 of 361 days2017: Good 313 of 362 days2017: Moderate 49 of 362 days2018: Good 304 of 356 days2018: Moderate 52 of 356 days20182019: Good 326 of 362 days2019: Moderate 36 of 362 days2020: Good 351 of 363 days2020: Moderate 12 of 363 days2021: Good 313 of 365 days2021: Moderate 52 of 365 days2022: Good 323 of 358 days2022: Moderate 35 of 358 days2023: Good 279 of 330 days2023: Moderate 45 of 330 days2023: Unhealthy for Sensitive Groups 4 of 330 days2023: Unhealthy 2 of 330 days20232024: Good 313 of 351 days2024: Moderate 38 of 351 days2025: Good 283 of 330 days2025: Moderate 47 of 330 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 year0501001501983: 90th percentile AQI 711984: 90th percentile AQI 1011985: 90th percentile AQI 841986: 90th percentile AQI 901987: 90th percentile AQI 1151988: 90th percentile AQI 1221989: 90th percentile AQI 771990: 90th percentile AQI 1001991: 90th percentile AQI 1011992: 90th percentile AQI 891993: 90th percentile AQI 931994: 90th percentile AQI 971995: 90th percentile AQI 1121996: 90th percentile AQI 1001997: 90th percentile AQI 971998: 90th percentile AQI 1261999: 90th percentile AQI 1262000: 90th percentile AQI 932001: 90th percentile AQI 1012002: 90th percentile AQI 1012003: 90th percentile AQI 872004: 90th percentile AQI 772005: 90th percentile AQI 852006: 90th percentile AQI 802007: 90th percentile AQI 842008: 90th percentile AQI 712009: 90th percentile AQI 542010: 90th percentile AQI 772011: 90th percentile AQI 802012: 90th percentile AQI 672013: 90th percentile AQI 562014: 90th percentile AQI 542015: 90th percentile AQI 582016: 90th percentile AQI 542017: 90th percentile AQI 522018: 90th percentile AQI 542019: 90th percentile AQI 502020: 90th percentile AQI 462021: 90th percentile AQI 542022: 90th percentile AQI 502023: 90th percentile AQI 582024: 90th percentile AQI 512025: 90th percentile AQI 581983: Median AQI 441984: Median AQI 441985: Median AQI 411986: Median AQI 421987: Median AQI 461988: Median AQI 441989: Median AQI 411990: Median AQI 461991: Median AQI 481992: Median AQI 441993: Median AQI 461994: Median AQI 461995: Median AQI 441996: Median AQI 461997: Median AQI 461998: Median AQI 501999: Median AQI 512000: Median AQI 442001: Median AQI 492002: Median AQI 442003: Median AQI 462004: Median AQI 442005: Median AQI 452006: Median AQI 462007: Median AQI 462008: Median AQI 442009: Median AQI 402010: Median AQI 442011: Median AQI 472012: Median AQI 442013: Median AQI 422014: Median AQI 432015: Median AQI 442016: Median AQI 412017: Median AQI 412018: Median AQI 392019: Median AQI 412020: Median AQI 372021: Median AQI 392022: Median AQI 402023: Median AQI 422024: Median AQI 412025: Median AQI 401983198819931998200320082013201820232025
  • 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
Ozone26982%
Fine particles (PM2.5)6118%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
2025330283470000405887Ozone
2024351313380000415190Ozone
20233302794542004258157Ozone
2022358323350000405093Ozone
2021365313520000395489Ozone
2020363351120000374655Ozone
2019362326360000415067Ozone
2018356304520000395490Ozone
2017362313490000415284Ozone
20163613025810004154108Ozone
2015361280810000445889Ozone
2014360291690000435480Ozone
2013357298590000425680Ozone
20123522499760004467140Ozone
201136021314250004780119Ozone
20103182119980004477140Ozone
20093613055420004054101Ozone
20083612579770004471136Ozone
200735421313290004684115Ozone
2006333203115150004680136Ozone
2005339220106130004585136Ozone
20043492469391004477154Ozone
200334120911895004687200Ozone
2002356221973260044101190Ozone
20013361831172970049101174Ozone
2000357216113271004493169Ozone
199934617110853140051126190Ozone
19983411739257154050126205Ozone
1997350202121234004697174Ozone
19963462071073110046100154Ozone
1995341194964470044112169Ozone
1994348207115251004697161Ozone
1993345201118242004693166Ozone
1992355221114191004489174Ozone
19913191721123230048101164Ozone
19903392011082640046100169Ozone
19893432419570004177126Ozone
19883371949723212044122221Ozone
1987364214944871046115202Ozone
198632123263251004290156Ozone
19851631193581004184161Ozone
198439278400044101122Ozone
1983179710004471108Ozone

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 Virginia with a similar median AQI in 2025

All monitored counties in Virginia

Source: U.S. EPA AirData, “Annual AQI by County” files for 1983–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem