SmogRank / Japan / Miyazaki / Mitai
Mitai, month by month
Mitai has a measured daily mean on 1,119 days since 28 July 2023. Its worst month was July 2025, at 56 US AQI (11.7 µg/m³), 894th of 2,889 cities on that month's world ranking. Its cleanest was July 2024, at 29 US AQI (5.3 µg/m³). 2025 averaged 51 US AQI (9.2 µg/m³), against 44 US AQI (8.0 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
2 months
| Month | Why |
|---|---|
| Nov 2025 | 16 of 30 days measured; a month needs 21. The others: 10 with no readings from the monitor, 4 with readings for part of the day (a day needs 18 hours). |
| Jul 2023 | 3 of 31 days measured; a month needs 22. The others: 1 with readings for part of the day (a day needs 18 hours). |
A day counts once 18 hours of it are measured; a month needs 70% of its days.
Mitai's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| July 2025 | 5611.7 µg/m³ | 894thof 2,889 | Japan and South Korea, June and July 2025 |
| March 2025 | 5611.6 µg/m³ | 1,299thof 2,862 | – |
| July 2026 | 5511.4 µg/m³ | 1,021stof 2,784 | Japan and South Korea, July 2026 |
| August 2024 | 5410.9 µg/m³ | 462ndof 2,010 | – |
| January 2025 | 5410.9 µg/m³ | 848thof 2,474 | – |
| April 2025 | 5310.3 µg/m³ | 1,108thof 2,951 | – |
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.
Mitai's worst days
| Day | US AQI | Episode |
|---|---|---|
| 4 Jul 2025 | 14453.0 µg/m³ | Japan and South Korea, June and July 2025 |
| 3 Jul 2025 | 13248.0 µg/m³ | Japan and South Korea, June and July 2025 |
| 2 Jul 2025 | 10336.5 µg/m³ | Japan and South Korea, June and July 2025 |
| 11 Feb 2024 | 9834.4 µg/m³ | Japan, 11 to 12 February 2024 |
| 21 Jul 2026 | 9834.2 µg/m³ | Japan and South Korea, July 2026 |
| 5 Jul 2025 | 9231.1 µg/m³ | Japan and South Korea, June and July 2025 |
| 23 Feb 2026 | 8929.5 µg/m³ | Japan, 23 February 2026 |
| 19 Jul 2026 | 8828.7 µg/m³ | Japan and South Korea, July 2026 |
| 29 Mar 2026 | 8728.2 µg/m³ | Japan and South Korea, March 2026 |
| 22 Jul 2026 | 8426.9 µg/m³ | Japan and South Korea, July 2026 |
Daily means, the highest since 28 Jul 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, Mitai, Japan, 28 Jul 2023 – 12 Oct 2026. Monitor data from Ministry of the Environment Air Pollutant Wide Area Monitoring System via OpenAQ; sources listed at smogrank.com/sources. smogrank.com/jp/mitai/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.
Mitai now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-12 18:07 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).