Mecca vs Mountain View: PM2.5 compared

Over the last year, Mecca's air was about 4.1× as polluted as Mountain View's: PM2.5 averaged 13.2 µg/m³ against 3.2, on the 35 days both cities were measured. Mecca had the dirtier air on 32 of those days, Mountain View on 1. Mecca was over the WHO's daily guideline of 15 µg/m³ on 13 of them, Mountain View on 0.

Right now

Mecca#242on the 24-hour board of 2,753, at 67 US AQI (17.5 µg/m³)

Mountain View#2,355on the 24-hour board of 2,753, at 16 US AQI (2.9 µg/m³)

The last year, day by day

Mecca

Mountain View

Each city's daily mean from 9 Oct 2025 to 8 Oct 2026, one stripe a day, coloured by band. A blank stripe is a day without a daily mean.

Month by month

Monthly means in µg/m³ over the days both cities were measured. Solid: Mecca. Faded: Mountain View. A month shows once both share 10 such days. Dashed line: the WHO daily guideline, 15 µg/m³.

Each city's worst days

Mecca

21 May 202614854.6 µg/m³
1 Oct 20268225.9 µg/m³
22 May 20267723.1 µg/m³

Mountain View

23 Sept 2026519.1 µg/m³
2 Oct 2026488.6 µg/m³
24 Sept 2026417.3 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

Mecca

Side by side with Indio (the nearest), Hanford (United States's 2nd worst on 30 days), Gujranwala (the world's worst on 30 days).

Mountain View

Side by side with Sunnyvale (the nearest), Gujranwala (the world's worst on 30 days).

Use this page

SmogRank, PM2.5 daily means compared, Mecca and Mountain View, 9 Oct 2025 – 8 Oct 2026, smogrank.com/compare/us-mecca/us-mountain-view (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).