Air quality in San Carlos, California, United States of America today

Update date
Last updated: 2026-01-25T09:00:00+00:00
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Mr. Duck’s Air Quality Score

Mr. Duck – Good air today

Good air today for San Carlos, Nuble Region, Chile

⚠️ 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 San Carlos, California is rated as Good today. The primary pollutant identified is PM2.5 (fine particles). Measurements reported by OpenAQ show a PM2.5 concentration of 0.0 µg/m³ based on five valid observations.

No other pollutants reached reporting thresholds, and PM10 data are not available for this 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).

Good
PM25
0
µg/m³
Info
PM1
0
µg/m³
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What the data includes

The dataset for San Carlos pulls from five recent sensor rows, all recorded at the same site – San Carlos Hills – with the newest reading timestamped on 2026‑01‑25 09:00 UTC. Five rows have been updated within the past thirty days, but none are from today or the last three days, so the most current snapshot is a little over two weeks old.

OpenAQ supplies measurements for five pollutants at this location. Both PM1 and PM2.5 report a value of 0.0 µg/m³, indicating no detected fine particulate matter in any of the recent samples. Relative humidity is recorded at 27.367833296457928 % across all rows, with the minimum, median and maximum identical, showing no observed fluctuation. Temperature is logged as 14.71016664505005 °C, again with a single consistent figure for every entry. The particle count metric UM003 registers 96.01699981689451 particles/cm³ uniformly throughout the dataset.

Because all five rows come from the same monitoring point, the data capture reflects conditions at one spot rather than city‑wide variation. The lack of spread in each pollutant’s values means the dataset cannot illustrate temporal changes or spatial differences within San Carlos. While the timestamps are relatively fresh—all within the last month—the absence of daily updates limits insight into short‑term dynamics, and users should keep in mind that air quality can differ across neighborhoods and times not covered 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).

PM25 0 µg/m³ PM1 0 µg/m³
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Data notes

The data shown for San Carlos reflects five valid measurements and is updated within 30 days, with the most recent reading recorded on 2026‑01‑25 at 09:00 UTC. While this snapshot provides a current view of citywide air quality, conditions can differ across neighborhoods and change throughout the day, so local variations may not be captured in these figures.

OpenAQ station rows

StationParameterValueUnitLast updated
San Carlos Hillspm10.0µg/m³2026-01-25 09:00 UTC
San Carlos Hillspm250.0µg/m³2026-01-25 09:00 UTC
San Carlos Hillsrelativehumidity27.367833296457928%2026-01-25 09:00 UTC
San Carlos Hillstemperature14.71016664505005c2026-01-25 09:00 UTC
San Carlos Hillsum00396.01699981689451particles/cm³2026-01-25 09:00 UTC