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

Highest daily Air Quality Index (US EPA) in Henry County was 140 in 1997, according to the U.S. Environmental Protection Agency. That is down 19 from 1996.

1997, index140
Change on 1996-19
Series high1691995
Series low1401997

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 Henry County, 1994 to 1997

14015016017019941995199619971994: 151 index1995: 169 index1996: 159 index1997: 140 index140150160170199419971994: 151 index1995: 169 index1996: 159 index1997: 140 index
index. Source: EPA, EPA AirData annual AQI by county: highest daily AQI. Retrieved 2026-10-12, published 2026-07-13.
All 4 values
Periodindex
1997140
1996159
1995169
1994151

Henry County compared with nearby places

Arlington County: 221 indexCaroline County: 195 indexCarroll County: 50 indexCharles City County: 202 indexChesterfield County: 172 indexCulpeper County: 66 indexFairfax County: 213 indexFauquier County: 174 indexFrederick County: 172 indexGiles County: 156 indexHanover County: 219 indexHenrico County: 195 indexHenry County: 140 indexKing William County: 59 indexLoudoun County: 33 indexMadison County: 174 indexNorthumberland County: 52 indexPrince Edward County: 159 indexPrince William County: 187 indexRoanoke County: 156 indexRockbridge County: 125 indexRockingham County: 54 indexSmyth County: 56 indexStafford County: 179 indexTazewell County: 44 indexWarren County: 62 indexWise County: 45 indexWythe County: 159 indexAlexandria city: 204 indexBristol city: 56 indexCharlottesville city: 47 indexChesapeake city: 57 indexCovington city: 53 indexFredericksburg city: 62 indexHampton city: 195 indexLynchburg city: 51 indexMartinsville city: 62 indexNewport News city: 61 indexNorfolk city: 78 indexRichmond city: 107 indexRoanoke city: 80 indexSuffolk city: 187 indexWinchester city: 67 index
  • Under 53
  • 53 to 62
  • 62 to 110
  • 110 to 170
  • 170 to 200
  • 200 and over
  • No data
Highest daily Air Quality Index (US EPA), 1997, index. Henry 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), Henry County, 1994 to 1997) [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), Henry County, 1994 to 1997. 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/henry-county-virginia. 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), Henry County, 1994 to 1997. 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/henry-county-virginia.

Harvard

U.S. Environmental Protection Agency (2026) EPA AirData annual AQI by county: highest daily AQI, Highest daily Air Quality Index (US EPA), Henry County, 1994 to 1997 [Dataset]. Available at: https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual, via Invokely: https://invokely.ai/en/highest-daily-air-quality-index/henry-county-virginia (Accessed: 12 October 2026).

BibTeX
@misc{environmental_highest_daily_air_quality_1997,
  author = {{U.S. Environmental Protection Agency}},
  title = {{EPA AirData annual AQI by county: highest daily AQI: Highest daily Air Quality Index (US EPA), Henry County, 1994 to 1997}},
  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/henry-county-virginia. 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), Henry County, 1994 to 1997
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/henry-county-virginia
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/en/highest-daily-air-quality-index/henry-county-virginia.
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 Henry County? Cite the source.
get_value {"indicator":"aqi_max","place":"us-county-51089"}
GET https://invokely.ai/api/v1/value?indicator=aqi_max&place=us-county-51089

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 Henry County?

Highest daily Air Quality Index (US EPA) in Henry County was 140 in 1997, according to the U.S. Environmental Protection Agency. That is down 19 from 1996.

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 Henry County?

169 in 1995, the highest value since 1994 in this series.

Related statistics for Henry County

All statistics for Henry County | Henry County in figures