SmogRank / United States / Kentucky / Louisville
Louisville, month by month
Louisville has a measured daily mean on 1,369 days since 1 January 2023. Its worst month was June 2023, at 77 US AQI (23.0 µg/m³), 214th of 1,603 cities on that month's world ranking. Its cleanest was September 2024, at 34 US AQI (6.1 µg/m³). 2025 averaged 48 US AQI (8.7 µg/m³), against 44 US AQI (7.9 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
Louisville's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| June 2023 | 7723.0 µg/m³ | 214thof 1,603 | Eastern United States and Canada, June and July 2023 United States and Canada, June 2023and 1 more |
| July 2023 | 6114.5 µg/m³ | 165thof 1,432 | United States and Canada, July 2023 North-eastern United States, 4 to 5 July 2023and 1 more |
| February 2026 | 5612.0 µg/m³ | 1,022ndof 2,866 | – |
| August 2023 | 5611.7 µg/m³ | 375thof 1,980 | – |
| November 2023 | 5511.5 µg/m³ | 358thof 2,243 | Eastern United States and Canada, November 2023 |
| June 2025 | 5511.1 µg/m³ | 990thof 2,508 | Northern United States and Canada, May and June 2025 |
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.
Louisville's worst days
| Day | US AQI | Episode |
|---|---|---|
| 28 Jun 2023 | 17183.5 µg/m³ | Eastern United States and Canada, June and July 2023 |
| 5 Jul 2025 | 12645.7 µg/m³ | North-eastern United States, July 2025 |
| 16 Jul 2023 | 12344.3 µg/m³ | United States and Canada, July 2023 |
| 17 Jul 2023 | 11741.8 µg/m³ | United States and Canada, July 2023 |
| 29 Jun 2023 | 11440.6 µg/m³ | Eastern United States and Canada, June and July 2023 |
| 15 Jun 2023 | 11239.8 µg/m³ | United States and Canada, June 2023 |
| 6 Jun 2023 | 9834.1 µg/m³ | Eastern United States and Canada, May and June 2023 |
| 8 Jun 2023 | 9432.2 µg/m³ | Eastern United States and Canada, May and June 2023 |
| 18 Jun 2023 | 9331.9 µg/m³ | United States and Canada, June 2023 |
| 27 Jun 2023 | 9130.7 µg/m³ | Eastern United States and Canada, June and July 2023 |
Daily means, the highest since 1 Jan 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, Louisville, United States, 1 Jan 2023 – 11 Oct 2026. Monitor data from AirNow, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/us/louisville/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.
Louisville 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).