SmogRank / United States / Oregon / The Dalles
The Dalles, month by month
The Dalles has a measured daily mean on 1,227 days since 7 May 2023. Its worst month was August 2023, at 70 US AQI (19.2 µg/m³), 137th of 1,980 cities on that month's world ranking. Its cleanest was April 2024, at 17 US AQI (3.0 µg/m³). 2025 averaged 31 US AQI (5.6 µg/m³), against 31 US AQI (5.5 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
The Dalles's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| August 2023 | 7019.2 µg/m³ | 137thof 1,980 | North-western United States and Canada, August 2023 |
| August 2026 | 6717.5 µg/m³ | 310thof 2,896 | North-western United States and Canada, 4 to 22 August 2026 North-western United States and Canada, July and August 2026 |
| January 2026 | 5410.6 µg/m³ | 1,021stof 2,617 | – |
| November 2023 | 519.1 µg/m³ | 845thof 2,243 | – |
| September 2025 | 498.8 µg/m³ | 951stof 3,104 | – |
| November 2025 | 468.3 µg/m³ | 1,456thof 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.
The Dalles's worst days
Daily means, the highest since 7 May 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, The Dalles, United States, 7 May 2023 – 11 Oct 2026. Monitor data from AirNow, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/us/the-dalles/history (accessed 13 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.
The Dalles now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-13 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).