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

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

Highest daily Air Quality Index (US EPA) in Brown County was 77 in 2025, according to the U.S. Environmental Protection Agency. That is unchanged from 2024.

2025, index77
Change on 20240
Series high1262023
Series low712014

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 Brown County, 2014 to 2025

60801001201402014201620182020202220252014: 71 index2015: 101 index2016: 101 index2017: 90 index2018: 97 index2019: 74 index2020: 80 index2021: 84 index2022: 97 index2023: 126 index2024: 77 index2025: 77 index608010012014020142018202220252014: 71 index2015: 101 index2016: 101 index2017: 90 index2018: 97 index2019: 74 index2020: 80 index2021: 84 index2022: 97 index2023: 126 index2024: 77 index2025: 77 index
index. Source: EPA, EPA AirData annual AQI by county: highest daily AQI. Retrieved 2026-10-12, published 2026-07-13.
All 12 values
Periodindex
202577
202477
2023126
202297
202184
202080
201974
201897
201790
2016101
2015101
201471

Brown County compared with nearby places

Allen County: 115 indexBartholomew County: 97 indexBoone County: 112 indexBrown County: 77 indexCarroll County: 105 indexClark County: 133 indexDelaware County: 108 indexDubois County: 88 indexElkhart County: 171 indexFloyd County: 126 indexGreene County: 90 indexHamilton County: 118 indexHendricks County: 90 indexHenry County: 95 indexHoward County: 122 indexKnox County: 93 indexLake County: 219 indexLaPorte County: 153 indexMadison County: 122 indexMarion County: 170 indexMonroe County: 84 indexPerry County: 84 indexPorter County: 136 indexPosey County: 105 indexSt. Joseph County: 127 indexShelby County: 105 indexSpencer County: 88 indexTippecanoe County: 95 indexVanderburgh County: 100 indexVigo County: 108 indexWabash County: 112 indexWarrick County: 97 indexWhitley County: 108 index
  • Under 90
  • 90 to 97
  • 97 to 110
  • 110 to 120
  • 120 to 130
  • 130 and over
  • No data
Highest daily Air Quality Index (US EPA), 2025, index. Brown 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), Brown County, 2014 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), Brown County, 2014 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/brown-county-indiana. 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), Brown County, 2014 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/brown-county-indiana.

Harvard

U.S. Environmental Protection Agency (2026) EPA AirData annual AQI by county: highest daily AQI, Highest daily Air Quality Index (US EPA), Brown County, 2014 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/brown-county-indiana (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), Brown County, 2014 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/brown-county-indiana. 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), Brown County, 2014 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/brown-county-indiana
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/en/highest-daily-air-quality-index/brown-county-indiana.
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 Brown County? Cite the source.
get_value {"indicator":"aqi_max","place":"us-county-18013"}
GET https://invokely.ai/api/v1/value?indicator=aqi_max&place=us-county-18013

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 Brown County?

Highest daily Air Quality Index (US EPA) in Brown County was 77 in 2025, according to the U.S. Environmental Protection Agency. That is unchanged 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 Brown County?

126 in 2023, the highest value since 2014 in this series.

Related statistics for Brown County

All statistics for Brown County | Brown County in figures