Air quality in Cheyenne, Wyoming, United States of America today

Mr. Duck’s Air Quality Score

Good air today for Cheyenne, Wyoming, United States of America

⚠️ This website is currently under active development. Some data may be incomplete or temporarily inaccurate. For health-critical decisions, please verify information through official government or environmental sources.

Categories follow US EPA AQI breakpoints for PM (estimate from latest valid measurements; this project does not compute EPA NowCast/24-hour AQI yet).

This friendly indicator summarizes the latest city readings. For health guidance, please see: EPA AirNow or WHO.

Air quality today

The air quality in Cheyenne, Wyoming is rated as Good today. The primary pollutant identified is PM2.5 (fine particles).

Measurements show a PM2.5 reference value of 1.0 µg/m³ and a PM10 reference value of 4.0 µg/m³ based on eight valid observations reported through OpenAQ. 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 Cheyenne air‑quality feed draws from 21 monitoring rows that report eight common pollutants: carbon monoxide (CO), nitrogen oxide (NO), nitrogen dioxide (NO₂), total oxides of nitrogen (NOX), ozone (O₃), fine particulate matter (PM₂.5), coarse particulate matter (PM₁₀) and sulfur dioxide (SO₂). All rows were last refreshed on 2026‑02‑10 at 23:00 UTC, so the most recent data are less than a week old across every measured species.

Across the dataset the observed concentrations span modest ranges. Ozone varies from 0.031 ppm up to 0.053 ppm with a median of 0.044 ppm, while nitrogen dioxide is recorded between 0.001 ppm and 0.010 ppm (median 0.003 ppm). Particulate matter shows the widest spread: PM₁₀ values range from 4 µg/m³ to 21 µg/m³ (median 7 µg/m³) and PM₂.5 from 1 µg/m³ to 5 µg/m³ (median 4.5 µg/m³). Carbon monoxide is measured between 0.1 ppm and 0.2 ppm (median 0.15 ppm), whereas sulfur dioxide hovers around zero, recorded from –0.001 ppm to 0.001 ppm with a median of exactly 0 ppm. Nitric oxide is very low, ranging from 0 ppm to 0.0006 ppm (median 0.0003 ppm), and NOX spans 0.0012 ppm to 0.0033 ppm (median 0.00225 ppm).

The coverage is uneven: all eight pollutants appear in the same set of rows, but the number of observations per pollutant differs slightly because some sensors report at higher resolution (three‑hourly for O₃, NO₂, PM₁₀ and PM₂.5) while others update less frequently (two‑hourly for CO, NO, NOX). Because every row is recent, the dataset reflects current conditions, yet the relatively small number of monitoring points means that local variations within Cheyenne may not be fully captured at any given moment.

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 current dataset for Cheyenne includes eight valid measurements and is marked as Updated within 3 days, with the most recent values recorded on 2026‑02‑10 at 23:00 UTC. This information reflects a single point in time; air quality can differ across neighborhoods and change throughout the day, so conditions you experience may not exactly match these figures.

OpenAQ station rows