SmogRank / United States / California / Indio
Indio, month by month
Indio has a measured daily mean on 1,173 days since 4 February 2023. Its worst month was July 2023, at 67 US AQI (17.9 µg/m³), 89th of 1,432 cities on that month's world ranking. Its cleanest was September 2026, at 26 US AQI (4.7 µg/m³). 2025 averaged 43 US AQI (7.7 µg/m³), against 52 US AQI (9.6 µg/m³) in 2024.
Every month since 2023
The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales
Months without a mean, and why
4 months
| Month | Why |
|---|---|
| Dec 2023 | No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks. |
| Nov 2023 | No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks. |
| Apr 2023 | 3 of 30 days measured; a month needs 21. The others: 27 with under 18 hours of readings or readings that failed our checks. |
| Mar 2023 | 18 of 31 days measured; a month needs 22. The others: 2 missing from OpenAQ's archive, 11 with under 18 hours of readings or readings that failed our checks. |
A day counts once 18 hours of it are measured; a month needs 70% of its days.
Indio's worst months
| Month | US AQI | World rank |
|---|---|---|
| July 2023 | 6717.9 µg/m³ | 89thof 1,432 |
| September 2023 | 6416.1 µg/m³ | 152ndof 2,176 |
| May 2023 | 6013.7 µg/m³ | 176thof 1,600 |
| May 2024 | 5712.4 µg/m³ | 442ndof 2,684 |
| June 2023 | 5712.3 µg/m³ | 531stof 1,603 |
| June 2024 | 5612.0 µg/m³ | 348thof 2,563 |
Monthly means over the days measured; finished months only. World rank: its place on that month's world ranking of every city with enough days. Each month opens that ranking.
Indio's worst days
| Day | US AQI | Episode |
|---|---|---|
| 31 Jul 2023 | 17082.7 µg/m³ | – |
| 15 Jul 2023 | 13449.1 µg/m³ | – |
| 23 Jul 2023 | 12244.2 µg/m³ | – |
| 14 Jul 2023 | 10637.6 µg/m³ | – |
| 18 May 2024 | 9633.4 µg/m³ | – |
| 30 May 2023 | 9331.7 µg/m³ | – |
| 4 Aug 2025 | 8627.9 µg/m³ | California and Nevada, United States, August 2025 |
| 16 Sept 2023 | 8527.5 µg/m³ | – |
| 17 May 2024 | 8527.4 µg/m³ | – |
| 24 Apr 2024 | 8326.4 µg/m³ | – |
Daily means, the highest since 4 Feb 2023; the WHO's daily guideline is 15 µg/m³. Each date opens that day's world ranking, and each episode the bad-air spell it was part of.
Use this history
SmogRank, PM2.5 monthly and daily means, Indio, United States, 4 Feb 2023 – 10 Oct 2026. Monitor data from AirNow, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/us/indio/history (accessed 12 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.
Indio now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-12 17:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index. Some low-cost readings: Sensor.Community, ODbL (data and licence). Some readings: Uzhydromet (Uzbekistan's Hydrometeorological Service); Department of Environment, Nepal; Vietnam's government monitors; Aurassure; Umhverfisstofnun (Environment Agency of Iceland); RMCAB (Secretaría Distrital de Ambiente, Bogotá); Love My Air (City and County of Denver), no reuse terms published (why we use them).