Data / Highest daily Air Quality Index (US EPA) / Monroe County

Highest daily Air Quality Index (US EPA) in Monroe County

Highest daily Air Quality Index (US EPA) in Monroe County was 49 in 1990, according to the U.S. Environmental Protection Agency. That is down 138 from 1989.

1990, index49
Change on 1989-138
Series high2081985
Series low491990

Next release: Tuesday, 13 July 2027, estimated by Invokely from past publication dates (low confidence), not announced by the publisher. Release calendar

Get an email when a new figure is out or this one is revised.
Keep it in a collection in your library.

Highest daily Air Quality Index (US EPA) in Monroe County, 1980 to 1990

0501001502002501980198219841986198819901980: 202 index1981: 151 index1982: 115 index1983: 185 index1984: 185 index1985: 208 index1986: 172 index1987: 185 index1988: 204 index1989: 187 index1990: 49 index0501001502002501980198419901980: 202 index1981: 151 index1982: 115 index1983: 185 index1984: 185 index1985: 208 index1986: 172 index1987: 185 index1988: 204 index1989: 187 index1990: 49 index
index. Source: EPA, EPA AirData annual AQI by county: highest daily AQI. Retrieved 2026-10-12, published 2026-07-13.
All 11 values
Periodindex
199049
1989187
1988204
1987185
1986172
1985208
1984185
1983185
1982115
1981151
1980202

Monroe County compared with nearby places

Adams County: 122 indexChampaign County: 133 indexColes County: 62 indexCook County: 172 indexDuPage County: 115 indexEffingham County: 147 indexJackson County: 59 indexJersey County: 200 indexKane County: 126 indexLake County: 164 indexLaSalle County: 124 indexLivingston County: 122 indexLogan County: 136 indexMcHenry County: 126 indexMacon County: 150 indexMacoupin County: 192 indexMadison County: 207 indexMonroe County: 49 indexPeoria County: 126 indexRandolph County: 171 indexRock Island County: 93 indexSt. Clair County: 201 indexSangamon County: 150 indexWill County: 122 indexWinnebago County: 143 index
  • Under 120
  • 120 to 130
  • 130 to 140
  • 140 to 170
  • 170 and over
  • No data
Highest daily Air Quality Index (US EPA), 1990, index. Monroe County is outlined. Same source and period for every area shown. Source: U.S. Environmental Protection Agency. Boundaries: U.S. Census Bureau cartographic boundary files.

Rankings

Definition

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.

Report a problem with this figure

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 (Highest daily Air Quality Index (US EPA), Monroe County, 1980 to 1990) [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, Highest daily Air Quality Index (US EPA), Monroe County, 1980 to 1990. U.S. Environmental Protection Agency, 13 July 2026, https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Invokely, https://invokely.ai/en/highest-daily-air-quality-index/monroe-county-illinois. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Environmental Protection Agency. 2026. EPA AirData annual AQI by county: highest daily AQI. Highest daily Air Quality Index (US EPA), Monroe County, 1980 to 1990. Dataset. Accessed October 12, 2026. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Also distributed by Invokely, https://invokely.ai/en/highest-daily-air-quality-index/monroe-county-illinois.

Harvard

U.S. Environmental Protection Agency (2026) EPA AirData annual AQI by county: highest daily AQI, Highest daily Air Quality Index (US EPA), Monroe County, 1980 to 1990 [Dataset]. Available at: https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual, via Invokely: https://invokely.ai/en/highest-daily-air-quality-index/monroe-county-illinois (Accessed: 12 October 2026).

BibTeX
@misc{environmental_highest_daily_air_quality_1990,
  author = {{U.S. Environmental Protection Agency}},
  title = {{EPA AirData annual AQI by county: highest daily AQI: Highest daily Air Quality Index (US EPA), Monroe County, 1980 to 1990}},
  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/en/highest-daily-air-quality-index/monroe-county-illinois. 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: Highest daily Air Quality Index (US EPA), Monroe County, 1980 to 1990
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/en/highest-daily-air-quality-index/monroe-county-illinois
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/en/highest-daily-air-quality-index/monroe-county-illinois.
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  -
Embed this chart

Paste this code into a web page or a blog post. The chart shows the latest figures as they are published, with the source and a link back to this page.

Sites that read oEmbed links, such as WordPress, can show the chart when you paste the link to this page.

Use this data in your AI agent

Invokely serves this figure to AI assistants through MCP and to code through a REST API, with the source and citation attached. Ask your assistant:

What is the latest highest daily Air Quality Index (US EPA) in Monroe County? Cite the source.
get_value {"indicator":"aqi_max","place":"us-county-17133"}
GET https://invokely.ai/api/v1/value?indicator=aqi_max&place=us-county-17133

Connect Claude, ChatGPT or Cursor in one step. The trial answers 25 calls a day without an account.

Questions

What is the highest daily Air Quality Index (US EPA) in Monroe County?

Highest daily Air Quality Index (US EPA) in Monroe County was 49 in 1990, according to the U.S. Environmental Protection Agency. That is down 138 from 1989.

Where does this figure come from?

U.S. Environmental Protection Agency. EPA AirData annual AQI by county: highest daily AQI. Retrieved by Invokely on 2026-10-12.

What was the highest highest daily Air Quality Index (US EPA) in Monroe County?

208 in 1985, the highest value since 1980 in this series.

Related statistics for Monroe County

All statistics for Monroe County | Monroe County in figures