EnviroNearby

Hennepin County, Minnesota air quality history

Daily Air Quality Index summaries from EPA monitors in Hennepin, Minnesota, 1980–2025.

58%
Good days in 2025
45
Median daily AQI, 2025
10
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 Hennepin, Minnesota on 365 days. 211 of those days (58%) were in the Good range, and the median daily AQI was 45. That median is higher than the typical monitored county in Minnesota (median 37 across 21 counties), and higher than the typical monitored U.S. county (40). The main pollutant was fine particles (PM2.5) on 284 days. Across the years with fuller monitoring, the share of Good days rose: an average of 54% in 1980–1982 versus 57% 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 166 of 364 days1980: Moderate 179 of 364 days1980: Unhealthy for Sensitive Groups 18 of 364 days1980: Unhealthy 1 of 364 days19801981: Good 190 of 364 days1981: Moderate 165 of 364 days1981: Unhealthy for Sensitive Groups 7 of 364 days1981: Unhealthy 2 of 364 days1982: Good 238 of 364 days1982: Moderate 126 of 364 days1983: Good 220 of 362 days1983: Moderate 140 of 362 days1983: Unhealthy for Sensitive Groups 2 of 362 days1984: Good 209 of 366 days1984: Moderate 157 of 366 days1985: Good 262 of 361 days1985: Moderate 99 of 361 days19851986: Good 283 of 365 days1986: Moderate 79 of 365 days1986: Unhealthy for Sensitive Groups 3 of 365 days1987: Good 274 of 365 days1987: Moderate 85 of 365 days1987: Unhealthy for Sensitive Groups 6 of 365 days1988: Good 160 of 366 days1988: Moderate 193 of 366 days1988: Unhealthy for Sensitive Groups 12 of 366 days1988: Unhealthy 1 of 366 days1989: Good 162 of 365 days1989: Moderate 194 of 365 days1989: Unhealthy for Sensitive Groups 9 of 365 days1990: Good 246 of 365 days1990: Moderate 117 of 365 days1990: Unhealthy for Sensitive Groups 2 of 365 days19901991: Good 307 of 365 days1991: Moderate 57 of 365 days1991: Unhealthy for Sensitive Groups 1 of 365 days1992: Good 328 of 366 days1992: Moderate 36 of 366 days1992: Unhealthy for Sensitive Groups 2 of 366 days1993: Good 311 of 365 days1993: Moderate 52 of 365 days1993: Unhealthy for Sensitive Groups 2 of 365 days1994: Good 292 of 365 days1994: Moderate 73 of 365 days1995: Good 314 of 365 days1995: Moderate 51 of 365 days19951996: Good 294 of 366 days1996: Moderate 72 of 366 days1997: Good 335 of 365 days1997: Moderate 30 of 365 days1998: Good 307 of 365 days1998: Moderate 56 of 365 days1998: Unhealthy for Sensitive Groups 2 of 365 days1999: Good 279 of 365 days1999: Moderate 84 of 365 days1999: Unhealthy for Sensitive Groups 2 of 365 days2000: Good 207 of 366 days2000: Moderate 150 of 366 days2000: Unhealthy for Sensitive Groups 8 of 366 days2000: Unhealthy 1 of 366 days20002001: Good 158 of 364 days2001: Moderate 201 of 364 days2001: Unhealthy for Sensitive Groups 5 of 364 days2002: Good 177 of 365 days2002: Moderate 187 of 365 days2002: Unhealthy for Sensitive Groups 1 of 365 days2003: Good 152 of 365 days2003: Moderate 209 of 365 days2003: Unhealthy for Sensitive Groups 4 of 365 days2004: Good 185 of 366 days2004: Moderate 178 of 366 days2004: Unhealthy for Sensitive Groups 3 of 366 days2005: Good 160 of 365 days2005: Moderate 199 of 365 days2005: Unhealthy for Sensitive Groups 4 of 365 days2005: Unhealthy 2 of 365 days20052006: Good 138 of 365 days2006: Moderate 225 of 365 days2006: Unhealthy for Sensitive Groups 2 of 365 days2007: Good 114 of 365 days2007: Moderate 246 of 365 days2007: Unhealthy for Sensitive Groups 4 of 365 days2007: Unhealthy 1 of 365 days2008: Good 168 of 366 days2008: Moderate 194 of 366 days2008: Unhealthy for Sensitive Groups 4 of 366 days2009: Good 196 of 365 days2009: Moderate 166 of 365 days2009: Unhealthy for Sensitive Groups 3 of 365 days2010: Good 212 of 365 days2010: Moderate 150 of 365 days2010: Unhealthy for Sensitive Groups 3 of 365 days20102011: Good 196 of 365 days2011: Moderate 169 of 365 days2012: Good 216 of 366 days2012: Moderate 149 of 366 days2012: Unhealthy for Sensitive Groups 1 of 366 days2013: Good 227 of 365 days2013: Moderate 138 of 365 days2014: Good 162 of 365 days2014: Moderate 203 of 365 days2015: Good 155 of 365 days2015: Moderate 207 of 365 days2015: Unhealthy for Sensitive Groups 3 of 365 days20152016: Good 198 of 366 days2016: Moderate 166 of 366 days2016: Unhealthy for Sensitive Groups 2 of 366 days2017: Good 166 of 365 days2017: Moderate 198 of 365 days2017: Unhealthy for Sensitive Groups 1 of 365 days2018: Good 175 of 365 days2018: Moderate 189 of 365 days2018: Unhealthy for Sensitive Groups 1 of 365 days2019: Good 187 of 365 days2019: Moderate 178 of 365 days2020: Good 206 of 366 days2020: Moderate 158 of 366 days2020: Unhealthy for Sensitive Groups 1 of 366 days2020: Unhealthy 1 of 366 days20202021: Good 213 of 365 days2021: Moderate 149 of 365 days2021: Unhealthy 3 of 365 days2022: Good 244 of 365 days2022: Moderate 121 of 365 days2023: Good 173 of 365 days2023: Moderate 175 of 365 days2023: Unhealthy for Sensitive Groups 14 of 365 days2023: Unhealthy 3 of 365 days2024: Good 243 of 366 days2024: Moderate 119 of 366 days2024: Unhealthy for Sensitive Groups 3 of 366 days2024: Unhealthy 1 of 366 days2025: Good 211 of 365 days2025: Moderate 144 of 365 days2025: Unhealthy for Sensitive Groups 4 of 365 days2025: Unhealthy 6 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 year0501001980: 90th percentile AQI 871981: 90th percentile AQI 771982: 90th percentile AQI 681983: 90th percentile AQI 681984: 90th percentile AQI 691985: 90th percentile AQI 631986: 90th percentile AQI 621987: 90th percentile AQI 691988: 90th percentile AQI 851989: 90th percentile AQI 771990: 90th percentile AQI 631991: 90th percentile AQI 541992: 90th percentile AQI 511993: 90th percentile AQI 541994: 90th percentile AQI 581995: 90th percentile AQI 541996: 90th percentile AQI 581997: 90th percentile AQI 481998: 90th percentile AQI 541999: 90th percentile AQI 612000: 90th percentile AQI 742001: 90th percentile AQI 742002: 90th percentile AQI 712003: 90th percentile AQI 722004: 90th percentile AQI 702005: 90th percentile AQI 722006: 90th percentile AQI 722007: 90th percentile AQI 732008: 90th percentile AQI 732009: 90th percentile AQI 712010: 90th percentile AQI 692011: 90th percentile AQI 682012: 90th percentile AQI 622013: 90th percentile AQI 662014: 90th percentile AQI 682015: 90th percentile AQI 662016: 90th percentile AQI 682017: 90th percentile AQI 672018: 90th percentile AQI 682019: 90th percentile AQI 652020: 90th percentile AQI 612021: 90th percentile AQI 662022: 90th percentile AQI 622023: 90th percentile AQI 802024: 90th percentile AQI 632025: 90th percentile AQI 711980: Median AQI 541981: Median AQI 501982: Median AQI 441983: Median AQI 451984: Median AQI 471985: Median AQI 401986: Median AQI 381987: Median AQI 401988: Median AQI 541989: Median AQI 531990: Median AQI 441991: Median AQI 401992: Median AQI 381993: Median AQI 381994: Median AQI 421995: Median AQI 401996: Median AQI 381997: Median AQI 351998: Median AQI 381999: Median AQI 382000: Median AQI 462001: Median AQI 532002: Median AQI 512003: Median AQI 532004: Median AQI 502005: Median AQI 532006: Median AQI 542007: Median AQI 552008: Median AQI 522009: Median AQI 482010: Median AQI 442011: Median AQI 482012: Median AQI 442013: Median AQI 432014: Median AQI 522015: Median AQI 522016: Median AQI 482017: Median AQI 522018: Median AQI 512019: Median AQI 492020: Median AQI 482021: Median AQI 452022: Median AQI 422023: Median AQI 522024: Median AQI 422025: 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)28478%
Ozone6217%
Nitrogen dioxide (NO₂)144%
Coarse particles (PM10)51%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
202536521114446004571178PM2.5
202436624311931004263166PM2.5
2023365173175143005280187PM2.5
20223652441210000426296PM2.5
202136521314903004566157PM2.5
202036620615811004861158PM2.5
20193651871780000496595PM2.5
201836517518910005168104PM2.5
201736516619810005267115PM2.5
201636619816620004868145PM2.5
201536515520730005266119PM2.5
20143651622030000526896PM2.5
20133652271380000436693PM2.5
201236621614910004462104PM2.5
20113651961690000486896PM2.5
201036521215030004469128PM2.5
200936519616630004871126PM2.5
200836616819440005273133PM2.5
200736511424641005573153PM2.5
200636513822520005472125PM2.5
200536516019942005372162PM2.5
200436618517830005070122PM2.5
200336515220940005372116PM2.5
200236517718710005171110PM2.5
200136415820150005374128PM2.5
200036620715081004674160PM2.5
19993652798420003861105NO2
19983653075620003854139NO2
1997365335300000354899NO2
1996366294720000385897NO2
1995365314510000405476NO2
1994365292730000425884NO2
19933653115220003854105NO2
19923663283620003851116NO2
19913653075710004054102NO2
199036524611720004463106CO
198936516219490005377143CO
1988366160193121005485180CO
19873652748560004069143CO
19863652837930003862112CO
1985361262990000406387CO
19843662091570000476993CO
198336222014020004568104CO
19823642381260000446896CO
198136419016572005077170CO
1980364166179181005487159CO

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 Minnesota with a similar median AQI in 2025

All monitored counties in Minnesota

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