SmogRank / United States / Michigan / Royal Oak
Royal Oak, month by month
Royal Oak has a measured daily mean on 324 days since 19 September 2025. Its worst month was July 2026, at 107 US AQI (37.9 µg/m³), 76th of 2,784 cities on that month's world ranking. Its cleanest was May 2026, at 36 US AQI (6.5 µg/m³).
Every month since 2025
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
5 months
| Month | Why |
|---|---|
| Oct 2026 | 2 of 11 days measured; a month needs 8. The others: 2 with no readings from the monitors, 1 with readings for part of the day (a day needs 18 hours), 6 with under 18 hours of readings or readings that failed our checks. |
| Sep 2026 | 16 of 30 days measured; a month needs 21. The others: 14 with under 18 hours of readings or readings that failed our checks. |
| Feb 2026 | 11 of 28 days measured; a month needs 20. The others: 17 with under 18 hours of readings or readings that failed our checks. |
| Jan 2026 | 21 of 31 days measured; a month needs 22. The others: 10 with under 18 hours of readings or readings that failed our checks. |
| Sep 2025 | 12 of 30 days measured; a month needs 21. |
A day counts once 18 hours of it are measured; a month needs 70% of its days.
Royal Oak's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| July 2026 | 10737.9 µg/m³ | 76thof 2,784 | Northern United States and Canada, July 2026 |
| March 2026 | 5812.8 µg/m³ | 1,092ndof 2,971 | – |
| December 2025 | 5712.5 µg/m³ | 914thof 3,006 | – |
| August 2026 | 5511.2 µg/m³ | 667thof 2,896 | – |
| October 2025 | 509.0 µg/m³ | 675thof 2,614 | – |
| November 2025 | 468.2 µg/m³ | 1,482ndof 2,715 | – |
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.
Royal Oak's worst days
| Day | US AQI | Episode |
|---|---|---|
| 16 Jul 2026 | 427289.0 µg/m³ | Northern United States and Canada, July 2026 |
| 17 Jul 2026 | 301225.5 µg/m³ | Northern United States and Canada, July 2026 |
| 15 Jul 2026 | 16575.4 µg/m³ | Northern United States and Canada, July 2026 |
| 19 Jul 2026 | 13549.4 µg/m³ | Northern United States and Canada, July 2026 |
| 18 Jul 2026 | 12445.0 µg/m³ | Northern United States and Canada, July 2026 |
| 6 Jan 2026 | 11541.2 µg/m³ | North-eastern United States and Canada around Milwaukee, 6 January 2026 |
| 20 Jul 2026 | 11440.6 µg/m³ | Northern United States and Canada, July 2026 |
| 5 Jan 2026 | 11139.7 µg/m³ | – |
| 3 Dec 2025 | 11039.3 µg/m³ | – |
| 18 Feb 2026 | 10537.2 µg/m³ | – |
Daily means, the highest since 19 Sept 2025; 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, Royal Oak, United States, 19 Sep 2025 – 11 Oct 2026. Monitor data from AirGradient via OpenAQ; sources listed at smogrank.com/sources. smogrank.com/us/royal-oak/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.
Royal Oak now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-12 21:07 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).