SmogRank / Japan / Kumamoto / Kikuchi
Kikuchi, month by month
Kikuchi has a measured daily mean on 859 days since 26 April 2024. Its worst month was July 2025, at 60 US AQI (13.7 µg/m³), 540th of 3,073 cities on that month's world ranking. Its cleanest was July 2024, at 29 US AQI (5.3 µg/m³).
Every month since 2024
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
1 month
| Month | Why |
|---|---|
| Apr 2024 | 5 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.
Kikuchi's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| July 2025 | 6013.7 µg/m³ | 540thof 3,073 | Japan and South Korea, June and July 2025 |
| January 2025 | 5913.4 µg/m³ | 684thof 2,754 | Japan and South Korea, 17 to 24 January 2025 |
| May 2024 | 5712.5 µg/m³ | 434thof 2,684 | South Korea and Japan, May 2024 |
| February 2026 | 5712.3 µg/m³ | 1,126thof 3,180 | – |
| March 2025 | 5712.2 µg/m³ | 1,345thof 3,102 | Japan and South Korea, February and March 2025 |
| March 2026 | 5611.9 µg/m³ | 1,396thof 3,285 | Japan and South Korea, March 2026 |
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.
Kikuchi's worst days
| Day | US AQI | Episode |
|---|---|---|
| 2 Jul 2025 | 15155.9 µg/m³ | Japan and South Korea, June and July 2025 |
| 3 Jul 2025 | 13248.2 µg/m³ | Japan and South Korea, June and July 2025 |
| 1 Jul 2025 | 12143.5 µg/m³ | Japan and South Korea, June and July 2025 |
| 4 Jul 2025 | 11039.1 µg/m³ | Japan and South Korea, June and July 2025 |
| 27 Feb 2025 | 9633.0 µg/m³ | Japan and South Korea, February and March 2025 |
| 28 Mar 2026 | 9231.3 µg/m³ | Japan and South Korea, March 2026 |
| 21 Jan 2025 | 9130.7 µg/m³ | Japan and South Korea, 17 to 24 January 2025 |
| 29 Mar 2026 | 8829.1 µg/m³ | Japan and South Korea, March 2026 |
| 7 Sept 2024 | 8728.3 µg/m³ | Japan and South Korea, September 2024 |
| 22 May 2024 | 8628.1 µg/m³ | South Korea and Japan, May 2024 |
Daily means, the highest since 26 Apr 2024; 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, Kikuchi, Japan, 26 Apr 2024 – 13 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/kikuchi/history (accessed 14 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.
Kikuchi now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-14 00:07 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).