SmogRank / United States / Missouri / Columbia
Columbia, month by month
Columbia, Missouri has a measured daily mean on 885 days since 5 March 2024. Its worst month was August 2025, at 65 US AQI (16.4 µg/m³), 295th of 2,901 cities on that month's world ranking. Its cleanest was June 2026, at 28 US AQI (5.0 µg/m³). 2025 averaged 56 US AQI (11.7 µg/m³), against 55 US AQI (11.4 µg/m³) in 2024.
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
3 months
| Month | Why |
|---|---|
| Feb 2025 | 17 of 28 days measured; a month needs 20. The others: 11 with under 18 hours of readings or readings that failed our checks. |
| Jan 2025 | 9 of 31 days measured; a month needs 22. The others: 22 with under 18 hours of readings or readings that failed our checks. |
| Mar 2024 | 17 of 31 days measured; a month needs 22. The others: 1 missing from OpenAQ's archive, 9 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.
Columbia's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| August 2025 | 6516.4 µg/m³ | 295thof 2,901 | North-eastern United States and Canada, 29 July to 9 August 2025 |
| August 2024 | 6415.9 µg/m³ | 155thof 2,010 | – |
| December 2024 | 6215.2 µg/m³ | 455thof 2,616 | – |
| June 2025 | 6215.1 µg/m³ | 433rdof 2,508 | Northern United States and Canada, June 2025 Northern United States and Canada, May and June 2025 |
| September 2025 | 6013.8 µg/m³ | 375thof 3,104 | – |
| July 2024 | 5913.2 µg/m³ | 283rdof 2,566 | – |
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.
Columbia's worst days
| Day | US AQI | Episode |
|---|---|---|
| 1 Aug 2025 | 16372.5 µg/m³ | North-eastern United States and Canada, 29 July to 9 August 2025 |
| 2 Aug 2025 | 12846.3 µg/m³ | North-eastern United States and Canada, 29 July to 9 August 2025 |
| 24 Dec 2024 | 11440.6 µg/m³ | – |
| 29 Oct 2024 | 11340.3 µg/m³ | – |
| 19 Aug 2024 | 10637.7 µg/m³ | – |
| 12 Feb 2025 | 10436.7 µg/m³ | – |
| 10 Jun 2025 | 10035.4 µg/m³ | Northern United States and Canada, June 2025 |
| 4 Sept 2025 | 9934.6 µg/m³ | – |
| 26 Jul 2024 | 9734.0 µg/m³ | – |
| 13 Mar 2025 | 9532.5 µg/m³ | – |
Daily means, the highest since 5 Mar 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, Columbia, Missouri, United States, 5 Mar 2024 – 11 Oct 2026. Monitor data from AirGradient via OpenAQ; sources listed at smogrank.com/sources. smogrank.com/us/columbia-missouri/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.
Columbia now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-12 20:07 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).