Air quality in Custer County, South Dakota, United States of America today
Mr. Duck’s Air Quality Score
Good air today for Custer County, South Dakota, United States of America
This friendly indicator summarizes the latest city readings. For health guidance, please see: EPA AirNow or WHO.
Air quality today
The air quality in Custer County, South Dakota is rated as Good today. The primary pollutant identified is PM2.5 (fine particles). Measurements from three valid samples show a PM2.5 reference value of 4.5 µg/m³ and a PM10 reference value of 0.0 µg/m³, as reported by OpenAQ.
Data for this assessment are based on the three recent observations recorded for the area. This page is informational; for health guidance, use official sources such as EPA AirNow or WHO.
Latest sensor values
PM categories follow US EPA AQI breakpoints, shown here as an estimate derived from the latest valid measurements (this project does not compute EPA NowCast/24-hour AQI yet).
What the data includes
The air‑quality record for Custer County, South Dakota is drawn from a single monitoring location – the WIND CAVE site – which supplies data on three pollutants: ozone (O₃), particulate matter up to 10 µm (PM10) and fine particulate matter up to 2.5 µm (PM2.5). All of the most recent observations were logged at the same moment, 2026‑02‑10 23:00 UTC, and each entry is flagged as having been updated within the past seven days, indicating that the dataset reflects a very current snapshot rather than historic or stale values.
The numeric range for each pollutant is narrow because only one measurement exists. Ozone registers at 0.046 ppm, with the minimum, median and maximum all equal to this figure, so there is no observed variability in the sample. PM10 reads exactly zero micrograms per cubic metre across the board, again showing a single‑point value without spread. In contrast, PM2.5 shows a measured concentration of 4.5 µg/m³, also identical for its minimum, median and maximum. Because there is only one row of data, typical or median values coincide with the sole reading, and no percentile distribution can be derived beyond the reported 10th and 90th percentiles, which match the same numbers.
With just one monitoring station contributing to the dataset, coverage across Custer County is limited; conditions elsewhere in the county may differ from those captured at WIND CAVE. The freshness of the timestamps is good – all three pollutants were recorded on the same recent date – but the lack of additional stations means that spatial representation is sparse. Consequently, while the current figures provide an exact snapshot for this location, they do not convey broader temporal trends or geographic variation within the county.
Learn more about sources and filtering: About the data.
Trusted references: WHO (Air pollution) · US EPA AirNow · European Environment Agency (Air)
Latest sensor values (bars)
PM categories follow US EPA AQI breakpoints, shown here as an estimate derived from the latest valid measurements (this project does not compute EPA NowCast/24-hour AQI yet).
Data notes
The data shown for Custer County reflects three valid measurements and was updated within 3 days, with the most recent reading recorded on 2026‑02‑10 at 23:00 UTC. This snapshot provides a brief view of current conditions; however, air quality can differ across neighborhoods and change throughout the day, so local variations may not be captured in these figures.
OpenAQ station rows
| Station | Parameter | Value | Unit | Last updated |
|---|---|---|---|---|
| WIND CAVE | o3 | 0.046 | ppm | 2026-02-10 23:00 UTC |
| WIND CAVE | pm10 | 0.0 | µg/m³ | 2026-02-10 23:00 UTC |
| WIND CAVE | pm25 | 4.5 | µg/m³ | 2026-02-10 23:00 UTC |