EnviroNearby

Onondaga County, New York air quality history

Daily Air Quality Index summaries from EPA monitors in Onondaga, New York, 1980–2025.

83%
Good days in 2025
36
Median daily AQI, 2025
4
Days above 100 in 2025
358
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Onondaga, New York on 358 days. 298 of those days (83%) were in the Good range, and the median daily AQI was 36. That median is about the same as the typical monitored county in New York (median 36 across 27 counties), and lower than the typical monitored U.S. county (40). The main pollutant was ozone on 249 days. Across the years with fuller monitoring, the share of Good days held roughly steady: an average of 82% in 1980–1982 versus 82% 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 294 of 366 days1980: Moderate 49 of 366 days1980: Unhealthy for Sensitive Groups 19 of 366 days1980: Unhealthy 3 of 366 days1980: Very Unhealthy 1 of 366 days19801981: Good 307 of 365 days1981: Moderate 40 of 365 days1981: Unhealthy for Sensitive Groups 12 of 365 days1981: Unhealthy 5 of 365 days1981: Very Unhealthy 1 of 365 days1982: Good 296 of 363 days1982: Moderate 45 of 363 days1982: Unhealthy for Sensitive Groups 15 of 363 days1982: Unhealthy 7 of 363 days1983: Good 314 of 365 days1983: Moderate 43 of 365 days1983: Unhealthy for Sensitive Groups 7 of 365 days1983: Unhealthy 1 of 365 days1984: Good 261 of 366 days1984: Moderate 99 of 366 days1984: Unhealthy for Sensitive Groups 5 of 366 days1984: Unhealthy 1 of 366 days1985: Good 252 of 363 days1985: Moderate 94 of 363 days1985: Unhealthy for Sensitive Groups 14 of 363 days1985: Unhealthy 2 of 363 days1985: Very Unhealthy 1 of 363 days19851986: Good 226 of 365 days1986: Moderate 113 of 365 days1986: Unhealthy for Sensitive Groups 21 of 365 days1986: Unhealthy 5 of 365 days1987: Good 221 of 365 days1987: Moderate 109 of 365 days1987: Unhealthy for Sensitive Groups 24 of 365 days1987: Unhealthy 10 of 365 days1987: Very Unhealthy 1 of 365 days1988: Good 246 of 365 days1988: Moderate 83 of 365 days1988: Unhealthy for Sensitive Groups 14 of 365 days1988: Unhealthy 20 of 365 days1988: Very Unhealthy 2 of 365 days1989: Good 265 of 365 days1989: Moderate 83 of 365 days1989: Unhealthy for Sensitive Groups 15 of 365 days1989: Unhealthy 2 of 365 days1990: Good 283 of 365 days1990: Moderate 65 of 365 days1990: Unhealthy for Sensitive Groups 14 of 365 days1990: Unhealthy 3 of 365 days19901991: Good 285 of 365 days1991: Moderate 58 of 365 days1991: Unhealthy for Sensitive Groups 12 of 365 days1991: Unhealthy 10 of 365 days1992: Good 305 of 366 days1992: Moderate 54 of 366 days1992: Unhealthy for Sensitive Groups 4 of 366 days1992: Unhealthy 3 of 366 days1993: Good 308 of 365 days1993: Moderate 49 of 365 days1993: Unhealthy for Sensitive Groups 6 of 365 days1993: Unhealthy 2 of 365 days1994: Good 305 of 365 days1994: Moderate 47 of 365 days1994: Unhealthy for Sensitive Groups 12 of 365 days1994: Unhealthy 1 of 365 days1995: Good 315 of 365 days1995: Moderate 40 of 365 days1995: Unhealthy for Sensitive Groups 5 of 365 days1995: Unhealthy 5 of 365 days19951996: Good 323 of 365 days1996: Moderate 39 of 365 days1996: Unhealthy for Sensitive Groups 3 of 365 days1997: Good 324 of 365 days1997: Moderate 31 of 365 days1997: Unhealthy for Sensitive Groups 8 of 365 days1997: Unhealthy 2 of 365 days1998: Good 308 of 365 days1998: Moderate 49 of 365 days1998: Unhealthy for Sensitive Groups 5 of 365 days1998: Unhealthy 3 of 365 days1999: Good 285 of 364 days1999: Moderate 58 of 364 days1999: Unhealthy for Sensitive Groups 17 of 364 days1999: Unhealthy 4 of 364 days2000: Good 275 of 366 days2000: Moderate 82 of 366 days2000: Unhealthy for Sensitive Groups 8 of 366 days2000: Unhealthy 1 of 366 days20002001: Good 252 of 365 days2001: Moderate 94 of 365 days2001: Unhealthy for Sensitive Groups 16 of 365 days2001: Unhealthy 3 of 365 days2002: Good 262 of 365 days2002: Moderate 77 of 365 days2002: Unhealthy for Sensitive Groups 18 of 365 days2002: Unhealthy 8 of 365 days2003: Good 311 of 365 days2003: Moderate 48 of 365 days2003: Unhealthy for Sensitive Groups 4 of 365 days2003: Unhealthy 2 of 365 days2004: Good 324 of 366 days2004: Moderate 41 of 366 days2004: Unhealthy for Sensitive Groups 1 of 366 days2005: Good 287 of 365 days2005: Moderate 63 of 365 days2005: Unhealthy for Sensitive Groups 13 of 365 days2005: Unhealthy 2 of 365 days20052006: Good 311 of 365 days2006: Moderate 50 of 365 days2006: Unhealthy for Sensitive Groups 4 of 365 days2007: Good 292 of 365 days2007: Moderate 58 of 365 days2007: Unhealthy for Sensitive Groups 14 of 365 days2007: Unhealthy 1 of 365 days2008: Good 300 of 366 days2008: Moderate 63 of 366 days2008: Unhealthy for Sensitive Groups 3 of 366 days2009: Good 321 of 365 days2009: Moderate 43 of 365 days2009: Unhealthy for Sensitive Groups 1 of 365 days2010: Good 308 of 365 days2010: Moderate 52 of 365 days2010: Unhealthy for Sensitive Groups 5 of 365 days20102011: Good 318 of 365 days2011: Moderate 45 of 365 days2011: Unhealthy for Sensitive Groups 2 of 365 days2012: Good 306 of 358 days2012: Moderate 44 of 358 days2012: Unhealthy for Sensitive Groups 8 of 358 days2013: Good 311 of 349 days2013: Moderate 38 of 349 days2014: Good 304 of 360 days2014: Moderate 56 of 360 days2015: Good 273 of 364 days2015: Moderate 91 of 364 days20152016: Good 314 of 366 days2016: Moderate 50 of 366 days2016: Unhealthy for Sensitive Groups 2 of 366 days2017: Good 310 of 365 days2017: Moderate 55 of 365 days2018: Good 297 of 364 days2018: Moderate 65 of 364 days2018: Unhealthy for Sensitive Groups 2 of 364 days2019: Good 301 of 365 days2019: Moderate 64 of 365 days2020: Good 300 of 364 days2020: Moderate 64 of 364 days20202021: Good 279 of 365 days2021: Moderate 85 of 365 days2021: Unhealthy for Sensitive Groups 1 of 365 days2022: Good 316 of 365 days2022: Moderate 49 of 365 days2023: Good 273 of 361 days2023: Moderate 80 of 361 days2023: Unhealthy for Sensitive Groups 4 of 361 days2023: Unhealthy 3 of 361 days2023: Very Unhealthy 1 of 361 days2024: Good 317 of 365 days2024: Moderate 48 of 365 days2025: Good 298 of 358 days2025: Moderate 56 of 358 days2025: Unhealthy for Sensitive Groups 4 of 358 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 year0501001980: 90th percentile AQI 741981: 90th percentile AQI 801982: 90th percentile AQI 771983: 90th percentile AQI 631984: 90th percentile AQI 741985: 90th percentile AQI 781986: 90th percentile AQI 871987: 90th percentile AQI 1001988: 90th percentile AQI 1001989: 90th percentile AQI 741990: 90th percentile AQI 671991: 90th percentile AQI 801992: 90th percentile AQI 581993: 90th percentile AQI 581994: 90th percentile AQI 641995: 90th percentile AQI 611996: 90th percentile AQI 541997: 90th percentile AQI 511998: 90th percentile AQI 641999: 90th percentile AQI 772000: 90th percentile AQI 672001: 90th percentile AQI 772002: 90th percentile AQI 812003: 90th percentile AQI 582004: 90th percentile AQI 542005: 90th percentile AQI 762006: 90th percentile AQI 562007: 90th percentile AQI 712008: 90th percentile AQI 582009: 90th percentile AQI 532010: 90th percentile AQI 582011: 90th percentile AQI 532012: 90th percentile AQI 582013: 90th percentile AQI 532014: 90th percentile AQI 542015: 90th percentile AQI 602016: 90th percentile AQI 532017: 90th percentile AQI 542018: 90th percentile AQI 582019: 90th percentile AQI 552020: 90th percentile AQI 542021: 90th percentile AQI 582022: 90th percentile AQI 522023: 90th percentile AQI 592024: 90th percentile AQI 532025: 90th percentile AQI 571980: Median AQI 361981: Median AQI 311982: Median AQI 321983: Median AQI 281984: Median AQI 321985: Median AQI 391986: Median AQI 451987: Median AQI 441988: Median AQI 411989: Median AQI 401990: Median AQI 391991: Median AQI 371992: Median AQI 351993: Median AQI 331994: Median AQI 361995: Median AQI 311996: Median AQI 311997: Median AQI 311998: Median AQI 311999: Median AQI 332000: Median AQI 352001: Median AQI 392002: Median AQI 372003: Median AQI 322004: Median AQI 282005: Median AQI 352006: Median AQI 312007: Median AQI 322008: Median AQI 352009: Median AQI 342010: Median AQI 342011: Median AQI 342012: Median AQI 352013: Median AQI 342014: Median AQI 352015: Median AQI 372016: Median AQI 362017: Median AQI 362018: Median AQI 372019: Median AQI 392020: Median AQI 372021: Median AQI 392022: Median AQI 372023: Median AQI 402024: Median AQI 352025: Median AQI 361980198519901995200020052010201520202025
  • 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
Ozone24970%
Fine particles (PM2.5)10930%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
20253582985640003657125Ozone
2024365317480000355384Ozone
20233612738043104059258Ozone
2022365316490000375269Ozone
20213652798510003958113Ozone
2020364300640000375474Ozone
2019365301640000395577Ozone
20183642976520003758115Ozone
2017365310550000365493Ozone
20163663145020003653122Ozone
2015364273910000376093Ozone
2014360304560000355493Ozone
2013349311380000345393Ozone
20123583064480003558133Ozone
20113653184520003453119Ozone
20103653085250003458140Ozone
20093653214310003453119Ozone
20083663006330003558150Ozone
200736529258141003271154Ozone
20063653115040003156122Ozone
200536528763132003576154Ozone
20043663244110002854102Ozone
20033653114842003258182Ozone
200236526277188003781182Ozone
200136525294163003977182Ozone
20003662758281003567179Ozone
199936428558174003377182Ozone
19983653084953003164156Ozone
19973653243182003151159Ozone
19963653233930003154129Ozone
19953653154055003161174Ozone
199436530547121003664169Ozone
19933653084962003358169Ozone
19923663055443003558154Ozone
1991365285581210003780185Ozone
199036528365143003967169Ozone
198936526583152004074166Ozone
19883652468314202041100207Ozone
198736522110924101044100208Ozone
1986365226113215004587164Ozone
198536325294142103978209CO
19843662619951003274168CO
19833653144371002863197Ozone
198236329645157003277197Ozone
198136530740125103180201Ozone
198036629449193103674201NO2

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 New York with a similar median AQI in 2025

All monitored counties in New York

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