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

Highest daily Air Quality Index (US EPA) in Cass County was 115 in 2025, according to the U.S. Environmental Protection Agency. That is up 7 from 2024.

2025, index115

Change on 2024+7

Series high2122002

Series low741981

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

Highest daily Air Quality Index (US EPA) in Cass County, 1980 to 2025

index. Source: EPA, EPA AirData annual AQI by county: highest daily AQI. Retrieved 2026-10-12, published 2026-07-13.

All 41 values

Period	index
2025	115
2024	108
2023	126
2022	119
2021	112
2020	122
2019	90
2018	126
2017	126
2016	129
2015	126
2014	115
2013	122
2012	203
2011	154
2010	108
2009	129
2008	115
2007	151
2006	133
2005	164
2004	143
2003	190
2002	212
2001	164
2000	166
1999	201
1998	192
1997	190
1996	200
1995	206
1994	201
1993	166
1992	187
1991	207
1985	164
1984	140
1983	202
1982	126
1981	74
1980	205

Cass County compared with nearby places

Under 110
110 to 140
140 to 150
150 to 160
160 and over
No data

Highest daily Air Quality Index (US EPA), 2025, index. Cass 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

Counties in Michigan by highest daily Air Quality Index (US EPA) 53 places

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), Cass County, 1980 to 2025) [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), Cass County, 1980 to 2025. 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/cass-county-michigan. 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), Cass County, 1980 to 2025. 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/cass-county-michigan.

Harvard

U.S. Environmental Protection Agency (2026) EPA AirData annual AQI by county: highest daily AQI, Highest daily Air Quality Index (US EPA), Cass County, 1980 to 2025 [Dataset]. Available at: https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual, via Invokely: https://invokely.ai/en/highest-daily-air-quality-index/cass-county-michigan (Accessed: 12 October 2026).

BibTeX

@misc{environmental_highest_daily_air_quality_2025,
  author = {{U.S. Environmental Protection Agency}},
  title = {{EPA AirData annual AQI by county: highest daily AQI: Highest daily Air Quality Index (US EPA), Cass County, 1980 to 2025}},
  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/cass-county-michigan. 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), Cass County, 1980 to 2025
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/cass-county-michigan
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/en/highest-daily-air-quality-index/cass-county-michigan.
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.

Embed code

<iframe src="https://invokely.ai/embed/highest-daily-air-quality-index/cass-county-michigan" width="760" height="440" title="Highest daily Air Quality Index (US EPA), Cass County, chart from Invokely" loading="lazy" style="border:0;width:100%;max-width:760px" referrerpolicy="strict-origin-when-cross-origin"></iframe>

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 Cass County? Cite the source.

get_value {"indicator":"aqi_max","place":"us-county-26027"}
GET https://invokely.ai/api/v1/value?indicator=aqi_max&place=us-county-26027

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 Cass County?

Highest daily Air Quality Index (US EPA) in Cass County was 115 in 2025, according to the U.S. Environmental Protection Agency. That is up 7 from 2024.

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 Cass County?

212 in 2002, the highest value since 1980 in this series.

Related statistics for Cass County

All statistics for Cass County | Cass County in figures