EnviroNearby

Vigo County, Indiana air quality history

Daily Air Quality Index summaries from EPA monitors in Vigo, Indiana, 1980–2025.

60%
Good days in 2025
45
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 Vigo, Indiana on 365 days. 218 of those days (60%) were in the Good range, and the median daily AQI was 45. That median is higher than the typical monitored county in Indiana (median 41 across 33 counties), and higher than the typical monitored U.S. county (40). The main pollutant was fine particles (PM2.5) on 224 days. Across the years with fuller monitoring, the share of Good days fell: an average of 99% in 1980–1982 versus 55% 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 244 of 244 days19801981: Good 341 of 343 days1981: Moderate 2 of 343 days1982: Good 331 of 335 days1982: Moderate 4 of 335 days1983: Good 281 of 341 days1983: Moderate 34 of 341 days1983: Unhealthy for Sensitive Groups 17 of 341 days1983: Unhealthy 9 of 341 days1984: Good 277 of 366 days1984: Moderate 58 of 366 days1984: Unhealthy for Sensitive Groups 25 of 366 days1984: Unhealthy 5 of 366 days1984: Very Unhealthy 1 of 366 days1985: Good 263 of 359 days1985: Moderate 76 of 359 days1985: Unhealthy for Sensitive Groups 15 of 359 days1985: Unhealthy 5 of 359 days19851986: Good 280 of 354 days1986: Moderate 59 of 354 days1986: Unhealthy for Sensitive Groups 12 of 354 days1986: Unhealthy 3 of 354 days1987: Good 179 of 271 days1987: Moderate 62 of 271 days1987: Unhealthy for Sensitive Groups 24 of 271 days1987: Unhealthy 6 of 271 days1988: Good 211 of 269 days1988: Moderate 52 of 269 days1988: Unhealthy for Sensitive Groups 6 of 269 days1989: Good 226 of 298 days1989: Moderate 53 of 298 days1989: Unhealthy for Sensitive Groups 14 of 298 days1989: Unhealthy 5 of 298 days1990: Good 232 of 313 days1990: Moderate 62 of 313 days1990: Unhealthy for Sensitive Groups 15 of 313 days1990: Unhealthy 4 of 313 days19901991: Good 229 of 312 days1991: Moderate 61 of 312 days1991: Unhealthy for Sensitive Groups 16 of 312 days1991: Unhealthy 6 of 312 days1992: Good 282 of 311 days1992: Moderate 27 of 311 days1992: Unhealthy for Sensitive Groups 2 of 311 days1993: Good 235 of 278 days1993: Moderate 39 of 278 days1993: Unhealthy for Sensitive Groups 4 of 278 days1994: Good 213 of 320 days1994: Moderate 59 of 320 days1994: Unhealthy for Sensitive Groups 35 of 320 days1994: Unhealthy 12 of 320 days1994: Very Unhealthy 1 of 320 days1995: Good 266 of 358 days1995: Moderate 63 of 358 days1995: Unhealthy for Sensitive Groups 26 of 358 days1995: Unhealthy 3 of 358 days19951996: Good 274 of 366 days1996: Moderate 43 of 366 days1996: Unhealthy for Sensitive Groups 31 of 366 days1996: Unhealthy 18 of 366 days1997: Good 293 of 364 days1997: Moderate 53 of 364 days1997: Unhealthy for Sensitive Groups 15 of 364 days1997: Unhealthy 3 of 364 days1998: Good 120 of 214 days1998: Moderate 74 of 214 days1998: Unhealthy for Sensitive Groups 17 of 214 days1998: Unhealthy 3 of 214 days1999: Good 114 of 229 days1999: Moderate 93 of 229 days1999: Unhealthy for Sensitive Groups 19 of 229 days1999: Unhealthy 3 of 229 days2000: Good 112 of 241 days2000: Moderate 120 of 241 days2000: Unhealthy for Sensitive Groups 8 of 241 days2000: Unhealthy 1 of 241 days20002001: Good 96 of 244 days2001: Moderate 121 of 244 days2001: Unhealthy for Sensitive Groups 26 of 244 days2001: Unhealthy 1 of 244 days2002: Good 90 of 243 days2002: Moderate 122 of 243 days2002: Unhealthy for Sensitive Groups 23 of 243 days2002: Unhealthy 8 of 243 days2003: Good 115 of 242 days2003: Moderate 116 of 242 days2003: Unhealthy for Sensitive Groups 9 of 242 days2003: Unhealthy 2 of 242 days2004: Good 127 of 244 days2004: Moderate 112 of 244 days2004: Unhealthy for Sensitive Groups 5 of 244 days2005: Good 109 of 244 days2005: Moderate 118 of 244 days2005: Unhealthy for Sensitive Groups 17 of 244 days20052006: Good 127 of 244 days2006: Moderate 110 of 244 days2006: Unhealthy for Sensitive Groups 7 of 244 days2007: Good 84 of 345 days2007: Moderate 244 of 345 days2007: Unhealthy for Sensitive Groups 17 of 345 days2008: Good 141 of 359 days2008: Moderate 216 of 359 days2008: Unhealthy for Sensitive Groups 2 of 359 days2009: Good 156 of 262 days2009: Moderate 106 of 262 days2010: Good 108 of 362 days2010: Moderate 252 of 362 days2010: Unhealthy for Sensitive Groups 2 of 362 days20102011: Good 114 of 360 days2011: Moderate 239 of 360 days2011: Unhealthy for Sensitive Groups 7 of 360 days2012: Good 125 of 355 days2012: Moderate 219 of 355 days2012: Unhealthy for Sensitive Groups 11 of 355 days2013: Good 149 of 362 days2013: Moderate 213 of 362 days2014: Good 136 of 354 days2014: Moderate 216 of 354 days2014: Unhealthy for Sensitive Groups 2 of 354 days2015: Good 165 of 362 days2015: Moderate 196 of 362 days2015: Unhealthy 1 of 362 days20152016: Good 180 of 363 days2016: Moderate 182 of 363 days2016: Unhealthy for Sensitive Groups 1 of 363 days2017: Good 153 of 365 days2017: Moderate 210 of 365 days2017: Unhealthy for Sensitive Groups 2 of 365 days2018: Good 188 of 365 days2018: Moderate 174 of 365 days2018: Unhealthy for Sensitive Groups 3 of 365 days2019: Good 161 of 365 days2019: Moderate 203 of 365 days2019: Unhealthy for Sensitive Groups 1 of 365 days2020: Good 223 of 366 days2020: Moderate 142 of 366 days2020: Unhealthy for Sensitive Groups 1 of 366 days20202021: Good 172 of 365 days2021: Moderate 193 of 365 days2022: Good 203 of 365 days2022: Moderate 160 of 365 days2022: Unhealthy for Sensitive Groups 2 of 365 days2023: Good 182 of 365 days2023: Moderate 175 of 365 days2023: Unhealthy for Sensitive Groups 6 of 365 days2023: Unhealthy 1 of 365 days2023: Very Unhealthy 1 of 365 days2024: Good 204 of 366 days2024: Moderate 161 of 366 days2024: Unhealthy for Sensitive Groups 1 of 366 days2025: Good 218 of 365 days2025: Moderate 146 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 301981: 90th percentile AQI 281982: 90th percentile AQI 301983: 90th percentile AQI 901984: 90th percentile AQI 971985: 90th percentile AQI 871986: 90th percentile AQI 711987: 90th percentile AQI 1011988: 90th percentile AQI 711989: 90th percentile AQI 801990: 90th percentile AQI 771991: 90th percentile AQI 901992: 90th percentile AQI 501993: 90th percentile AQI 641994: 90th percentile AQI 1221995: 90th percentile AQI 871996: 90th percentile AQI 1151997: 90th percentile AQI 801998: 90th percentile AQI 971999: 90th percentile AQI 1002000: 90th percentile AQI 822001: 90th percentile AQI 1052002: 90th percentile AQI 1122003: 90th percentile AQI 842004: 90th percentile AQI 802005: 90th percentile AQI 972006: 90th percentile AQI 782007: 90th percentile AQI 872008: 90th percentile AQI 742009: 90th percentile AQI 692010: 90th percentile AQI 782011: 90th percentile AQI 822012: 90th percentile AQI 792013: 90th percentile AQI 692014: 90th percentile AQI 702015: 90th percentile AQI 672016: 90th percentile AQI 672017: 90th percentile AQI 672018: 90th percentile AQI 672019: 90th percentile AQI 672020: 90th percentile AQI 612021: 90th percentile AQI 672022: 90th percentile AQI 632023: 90th percentile AQI 692024: 90th percentile AQI 642025: 90th percentile AQI 651980: Median AQI 191981: Median AQI 161982: Median AQI 191983: Median AQI 251984: Median AQI 341985: Median AQI 311986: Median AQI 331987: Median AQI 411988: Median AQI 391989: Median AQI 321990: Median AQI 381991: Median AQI 381992: Median AQI 311993: Median AQI 361994: Median AQI 381995: Median AQI 311996: Median AQI 291997: Median AQI 271998: Median AQI 481999: Median AQI 512000: Median AQI 532001: Median AQI 582002: Median AQI 582003: Median AQI 522004: Median AQI 482005: Median AQI 542006: Median AQI 502007: Median AQI 582008: Median AQI 542009: Median AQI 442010: Median AQI 572011: Median AQI 582012: Median AQI 552013: Median AQI 532014: Median AQI 542015: Median AQI 522016: Median AQI 512017: Median AQI 522018: Median AQI 502019: Median AQI 522020: Median AQI 462021: Median AQI 512022: Median AQI 472023: Median AQI 512024: Median AQI 472025: Median AQI 451980198519901995200020052010201520202025
  • 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)22461%
Ozone14139%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
202536521814610004565108PM2.5
202436620416110004764112PM2.5
202336518217561105169232PM2.5
202236520316020004763115PM2.5
20213651721930000516799PM2.5
202036622314210004661112PM2.5
201936516120310005267102PM2.5
201836518817430005067115PM2.5
201736515321020005267105PM2.5
201636318018210005167108PM2.5
201536216519601005267151PM2.5
201435413621620005470134PM2.5
20133621492130000536997PM2.5
2012355125219110005579136PM2.5
201136011423970005882127PM2.5
201036210825220005778115PM2.5
20092621561060000446993Ozone
200835914121620005474115PM2.5
200734584244170005887150PM2.5
200624412711070005078119Ozone
2005244109118170005497150Ozone
200424412711250004880126Ozone
200324211511692005284161Ozone
2002243901222380058112197Ozone
2001244961212610058105161Ozone
200024111212081005382154Ozone
1999229114931930051100166Ozone
199821412074173004897169Ozone
199736429353153002780185Ozone
19963662744331180029115200Ozone
199535826663263003187164Ozone
19943202135935121038122207Ozone
19932782353940003664129Ozone
19923112822720003150115PM10
199131222961166003890192PM10
199031323262154003877174Ozone
198929822653145003280182PM10
19882692115260003971126Ozone
1987271179622460041101190Ozone
198635428059123003371159Ozone
198535926376155003187177Ozone
198436627758255103497202Ozone
198334128134179002590200NO2
198233533140000193067NO2
198134334120000162857NO2
198024424400000193047NO2

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 Indiana with a similar median AQI in 2025

All monitored counties in Indiana

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