Counties in Minnesota by highest daily Air Quality Index (US EPA)

Ramsey County had the highest highest daily Air Quality Index (US EPA) of 21 counties in 2014, at 124. Cook County had the lowest, at 67. The median was 93. Source: the U.S. Environmental Protection Agency.

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Highest124Ramsey County
Lowest67Cook County
Median9321 counties

Map of counties, 2014

Anoka County: 93 indexBecker County: 97 indexBeltrami County: 69 indexCarlton County: 87 indexCook County: 67 indexCrow Wing County: 80 indexDakota County: 88 indexGoodhue County: 97 indexHennepin County: 96 indexLake County: 93 indexLyon County: 109 indexMille Lacs County: 77 indexOlmsted County: 103 indexRamsey County: 124 indexRock County: 101 indexSt. Louis County: 84 indexScott County: 90 indexStearns County: 89 indexWashington County: 98 indexWinona County: 110 indexWright County: 112 index
  • Under 84
  • 84 to 90
  • 90 to 97
  • 97 to 100
  • 100 and over
  • No data
index, 2014. Hatched areas have no value for this period. Source: EPA, EPA AirData annual AQI by county: highest daily AQI. Boundaries: U.S. Census Bureau cartographic boundary files.

All counties, 2014

Ramsey County: 124 indexRamsey County124Wright County: 112 indexWright County112Winona County: 110 indexWinona County110Lyon County: 109 indexLyon County109Olmsted County: 103 indexOlmsted County103Rock County: 101 indexRock County101Washington County: 98 indexWashington County98Becker County: 97 indexBecker County97Goodhue County: 97 indexGoodhue County97Hennepin County: 96 indexHennepin County96Anoka County: 93 indexAnoka County93Lake County: 93 indexLake County93Scott County: 90 indexScott County90Stearns County: 89 indexStearns County89Dakota County: 88 indexDakota County88Carlton County: 87 indexCarlton County87St. Louis County: 84 indexSt. Louis County84Crow Wing County: 80 indexCrow Wing County80Mille Lacs County: 77 indexMille Lacs County77Beltrami County: 69 indexBeltrami County69Cook County: 67 indexCook County67Ramsey County: 124 indexRamsey County124Wright County: 112 indexWright County112Winona County: 110 indexWinona County110Lyon County: 109 indexLyon County109Olmsted County: 103 indexOlmsted County103Rock County: 101 indexRock County101Washington County: 98 indexWashington County98Becker County: 97 indexBecker County97Goodhue County: 97 indexGoodhue County97Hennepin County: 96 indexHennepin County96Anoka County: 93 indexAnoka County93Lake County: 93 indexLake County93Scott County: 90 indexScott County90Stearns County: 89 indexStearns County89Dakota County: 88 indexDakota County88Carlton County: 87 indexCarlton County87St. Louis County: 84 indexSt. Louis County84Crow Wing County: 80 indexCrow Wing County80Mille Lacs County: 77 indexMille Lacs County77Beltrami County: 69 indexBeltrami County69Cook County: 67 indexCook County67
index. Source: EPA, EPA AirData annual AQI by county: highest daily AQI. Retrieved 2026-10-12.

Full ranking

Other periods

About this ranking

Highest daily Air Quality Index (AQI) value recorded in a US county during the year, from the EPA AirData annual summaries. Values above 500 are beyond the AQI scale and are published as EPA computes them.

A single day decides the value, so one wildfire or dust event can set it. Dust from the dry Owens Lake bed puts Inyo and Mono counties in California in the thousands. United States counties with air quality monitors only, about 1,000 of some 3,100 in recent years; a county without monitors has no value. The number of days with an AQI differs between counties because some monitors run only in the ozone season.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. 19 counties with data in other periods have no value for 2014 and are left out rather than filled from another source. Equal values share a rank.

How to cite

U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: highest daily AQI. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.

Citation styles

The publisher is the author. Invokely is named only as the place the figures were read, where a style asks for it.

APA 7

U.S. Environmental Protection Agency. (2026). EPA AirData annual AQI by county: highest daily AQI (Counties in Minnesota by highest daily Air Quality Index (US EPA), 2014) [Data set]. Retrieved October 12, 2026, from https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual

MLA 9

EPA AirData annual AQI by county: highest daily AQI, Counties in Minnesota by highest daily Air Quality Index (US EPA), 2014. U.S. Environmental Protection Agency, 13 July 2026, https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Invokely, https://invokely.ai/rankings/highest-daily-air-quality-index/minnesota-counties?period=2014. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Environmental Protection Agency. 2026. EPA AirData annual AQI by county: highest daily AQI. Counties in Minnesota by highest daily Air Quality Index (US EPA), 2014. Dataset. Accessed October 12, 2026. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Also distributed by Invokely, https://invokely.ai/rankings/highest-daily-air-quality-index/minnesota-counties?period=2014.

Harvard

U.S. Environmental Protection Agency (2026) EPA AirData annual AQI by county: highest daily AQI, Counties in Minnesota by highest daily Air Quality Index (US EPA), 2014 [Dataset]. Available at: https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual, via Invokely: https://invokely.ai/rankings/highest-daily-air-quality-index/minnesota-counties?period=2014 (Accessed: 12 October 2026).

BibTeX
@misc{environmental_counties_in_minnesota_by_2014,
  author = {{U.S. Environmental Protection Agency}},
  title = {{EPA AirData annual AQI by county: highest daily AQI: Counties in Minnesota by highest daily Air Quality Index (US EPA), 2014}},
  year = {2026},
  howpublished = {Data set},
  url = {https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual},
  urldate = {2026-10-12},
  note = {Accessed via Invokely, https://invokely.ai/rankings/highest-daily-air-quality-index/minnesota-counties?period=2014. Publisher attribution: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: highest daily AQI. https://aqs.epa.gov/aqsweb/airdata/download\_files.html\#Annual. Retrieved 2026-10-12.},
}
RIS
TY  - DATA
AU  - U.S. Environmental Protection Agency
TI  - EPA AirData annual AQI by county: highest daily AQI: Counties in Minnesota by highest daily Air Quality Index (US EPA), 2014
PY  - 2026
DA  - 2026/07/13
PB  - U.S. Environmental Protection Agency
DB  - Invokely
UR  - https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual
L2  - https://invokely.ai/rankings/highest-daily-air-quality-index/minnesota-counties?period=2014
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/highest-daily-air-quality-index/minnesota-counties?period=2014.
N1  - Publisher attribution: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: highest daily AQI. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.
ER  - 
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Rank Counties in Minnesota by highest daily Air Quality Index (US EPA) using official data, and cite the source.
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Questions

Which county has the highest highest daily Air Quality Index (US EPA)?

Ramsey County, with 124 in 2014, according to the U.S. Environmental Protection Agency.

Which county has the lowest highest daily Air Quality Index (US EPA)?

Cook County, with 67 in 2014.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Environmental Protection Agency, EPA AirData annual AQI by county: highest daily AQI. Retrieved 2026-10-12. 19 counties have no value for 2014 and are not ranked.

Highest daily Air Quality Index (US EPA): other rankings

Counties in Minnesota: more rankings