Air quality in Arcata, California, United States of America today
Mr. Duck’s Air Quality Score
Good air today for Arcata, California, 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 today in Arcata, California is rated as Good. The primary pollutant measured is PM2.5, with a recorded concentration of 6.30 µg/m³ based on five valid observations from OpenAQ data.
Five recent measurements support this assessment, confirming that fine particulate levels remain low. 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
Arcata’s OpenAQ feed currently includes six measured variables from a single monitoring location, Sunny Brae. The dataset contains one row for each pollutant, so the city’s air‑quality picture is based on a single station. All values are reported as a single measurement rather than a range, because each variable has identical minimum, median and maximum figures in the latest download.
The most recent data were recorded on 2026‑02‑11 00:00 UTC for PM1 (3.51 µg/m³), PM2.5 (6.30 µg/m³), relative humidity (64.29 %), temperature (14.87 °C) and particle count UM003 (733.22 particles/cm³). These five parameters are flagged as “updated within 7 days,” indicating they reflect conditions from the last few days. In contrast, PM10’s latest entry dates back to 2025‑01‑13 23:00 UTC and is labeled “old data,” showing a gap of more than a year for that metric.
Because each pollutant has only one recorded value, there is no observable spread or variability within the dataset; the reported median equals both the minimum and maximum. The uniformity of the numbers means the current snapshot cannot reveal fluctuations over time or differences across neighborhoods. Moreover, with just one monitoring site, Arcata’s air‑quality profile may not capture spatial variations that can occur elsewhere in the city. Users should keep in mind that the available data are limited both in geographic coverage and, for PM10, in recency.
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 Arcata, California reflects five valid measurements and was updated today (2026‑02‑11T00:00:00+00:00). This snapshot represents the most recent readings available from our monitoring network, but air quality can differ across neighborhoods and change throughout the day. Use this information as a general guide rather than a precise condition for any specific location or moment within the city.
OpenAQ station rows
| Station | Parameter | Value | Unit | Last updated |
|---|---|---|---|---|
| Sunny Brae | pm1 | 3.513333320617676 | µg/m³ | 2026-02-11 00:00 UTC |
| Sunny Brae | pm10 | 0.7360833361744881 | µg/m³ | 2025-01-13 23:00 UTC |
| Sunny Brae | pm25 | 6.303166675567628 | µg/m³ | 2026-02-11 00:00 UTC |
| Sunny Brae | relativehumidity | 64.29133326212565 | % | 2026-02-11 00:00 UTC |
| Sunny Brae | temperature | 14.869999837875367 | c | 2026-02-11 00:00 UTC |
| Sunny Brae | um003 | 733.2166666666666 | particles/cm³ | 2026-02-11 00:00 UTC |