Air quality in Winterthur, Zurich, Switzerland today

Mr. Duck’s Air Quality Score

Good air today for Winterthur, Zurich, Switzerland

⚠️ 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 Winterthur today is classified as Good. The primary pollutant identified is PM2.5 (fine particles). Measurements show a PM2.5 reference value of 8.47 µg/m³ and a PM10 reference value of 13.09 µg/m³, based on 21 valid observations collected via OpenAQ.

Overall conditions meet the Good category criteria according to the latest assessment. 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

Winterthur’s open‑air quality feed contains eight measured variables – nitrogen dioxide (NO2), ozone (O3), particulate matter of three size fractions (PM1, PM2.5 and PM10), relative humidity, temperature and particle number concentration (UM003). The dataset is built from 33 rows supplied by six stations, but the distribution across pollutants is uneven. For PM1, PM2.5, relative humidity, temperature and UM003 there are five recent records each, all refreshed on 2026‑02‑10 at 22:00 UTC, whereas PM10, NO2 and O3 have only three to four rows that were last updated on 2026‑02‑10 at 21:00 UTC. The remaining 11 rows carry an “unknown” freshness label, meaning a sizable share of the city’s data is not current.

Across the recent measurements the observed ranges are fairly wide. PM1 values span from about 0.55 µg/m³ up to 23.75 µg/m³ with a median near 4.29 µg/m³; PM2.5 varies between roughly 2.30 and 37.78 µg/m³, the middle value being 7.41 µg/m³; PM10 shows a minimum of 1.10 and a maximum of 38.28 µg/m³, with a median of 12.64 µg/m³. Temperature recorded at the Hegi site ranges from just under 6 °C to 21 °C, median 10.09 °C, while relative humidity runs from about 58 % to 89 %, median 62 %. The particle number concentration (UM003) is especially variable, from roughly 249 to almost 4 000 particles/cm³, with a typical value of 394 particles/cm³.

The most recent data points illustrate the freshest snapshot available: PM1, PM2.5, humidity, temperature and UM003 are all dated 2026‑02‑10 22:00 UTC; PM10, NO2 and O3 are one hour older at 2026‑02‑10 21:00 UTC. Because a notable fraction of rows lack recent timestamps, the picture presented reflects conditions at specific monitoring sites rather than a citywide average, and actual air quality can differ across neighborhoods and times not captured by these measurements.

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 set for Winterthur includes 21 valid measurements and is marked as Updated within 3 days, with the latest values recorded on 2026‑02‑10T22:00:00+00:00. These figures represent a snapshot of conditions at the time of collection; air quality can differ across neighbourhoods and change throughout the day, so individual experiences may vary from the reported averages.

OpenAQ station rows