SmogRank / Arvada / Westminster
Arvada vs Westminster: PM2.5 compared
Over the last year, Arvada and Westminster had about the same air: PM2.5 averaged 5.3 and 5.2 µg/m³, on the 54 days both cities were measured. Arvada had the dirtier air on 25 of those days, Westminster on 28. Arvada was over the WHO's daily guideline of 15 µg/m³ on 2 of them, Westminster on 2.
Right now
The last year, day by day
Month by month
Each city's worst days
Arvada
- 28 Jun 20268226.0 µg/m³
- 1 Jul 20267521.9 µg/m³
- 26 Apr 20265812.6 µg/m³
Westminster
- 1 Jul 20267019.3 µg/m³
- 28 Jun 20266918.7 µg/m³
- 15 Sept 20265310.1 µg/m³
Daily means in US AQI, with µg/m³ beside them, since the index stops at its top value, over the days both cities were measured in the last year. Each date opens that day's world board.
Compare either city with another
Arvada
Side by side with Mecca (United States's worst on 30 days), Gujranwala (the world's worst on 30 days).
Westminster
Side by side with Mecca (United States's worst on 30 days), Gujranwala (the world's worst on 30 days).
Use this page
SmogRank, PM2.5 daily means compared, Arvada and Westminster, 9 Oct 2025 – 8 Oct 2026, smogrank.com/compare/us-arvada/us-westminster (accessed 9 Oct 2026).
You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.
The same rules as every SmogRank figure: reference monitors first, and a day counts with 18 measured hours. How we measure.
Updated 2026-10-09 12:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index. Some readings: Uzhydromet (Uzbekistan's Hydrometeorological Service); Department of Environment, Nepal; Vietnam's government monitors; Aurassure; Umhverfisstofnun (Environment Agency of Iceland); Love My Air (City and County of Denver), no reuse terms published (why we use them).