SmogRank / Canada / British Columbia / Castlegar
Castlegar, month by month
Castlegar has a measured daily mean on 1,247 days since 1 January 2023. Its worst month was August 2026, at 110 US AQI (39.3 µg/m³), 48th of 2,896 cities on that month's world ranking. Its cleanest was May 2024, at 22 US AQI (4.0 µg/m³). 2025 averaged 42 US AQI (7.5 µg/m³), against 39 US AQI (7.1 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
4 months
| Month | Why |
|---|---|
| Jan 2026 | 15 of 31 days measured; a month needs 22. The others: 16 with no readings from the monitor. |
| Dec 2023 | 18 of 31 days measured; a month needs 22. The others: 12 with no readings from the monitor, 1 with readings for part of the day (a day needs 18 hours). |
| Mar 2023 | 11 of 31 days measured; a month needs 22. The others: 20 missing from OpenAQ's archive. |
| Feb 2023 | 1 of 28 days measured; a month needs 20. The others: 2 with readings for part of the day (a day needs 18 hours), 25 missing from OpenAQ's archive. |
A day counts once 18 hours of it are measured; a month needs 70% of its days.
Castlegar's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| August 2026 | 11039.3 µg/m³ | 48thof 2,896 | North-western United States and Canada, 4 to 22 August 2026 North-western United States and Canada, July and August 2026 |
| August 2023 | 9130.6 µg/m³ | 55thof 1,980 | North-western United States and Canada, August 2023 |
| September 2025 | 7522.1 µg/m³ | 172ndof 3,104 | North-western United States and Canada, September 2025 North-western Canada and United States, September 2025and 1 more |
| July 2026 | 7119.7 µg/m³ | 342ndof 2,784 | North-western United States and Canada, July and August 2026 |
| November 2023 | 6717.7 µg/m³ | 102ndof 2,243 | North-western United States and Canada, October and November 2023 |
| July 2024 | 5913.3 µg/m³ | 274thof 2,566 | North-western United States and Canada, July 2024 |
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.
Castlegar's worst days
| Day | US AQI | Episode |
|---|---|---|
| 11 Aug 2026 | 227152.0 µg/m³ | North-western United States and Canada, 4 to 22 August 2026 |
| 19 Aug 2023 | 217142.0 µg/m³ | North-western United States and Canada, August 2023 |
| 17 Aug 2023 | 205130.0 µg/m³ | North-western United States and Canada, August 2023 |
| 9 Aug 2026 | 193116.0 µg/m³ | North-western United States and Canada, 4 to 22 August 2026 |
| 20 Aug 2023 | 189110.0 µg/m³ | North-western United States and Canada, August 2023 |
| 7 Aug 2026 | 187107.0 µg/m³ | North-western United States and Canada, 4 to 22 August 2026 |
| 28 Nov 2023 | 185104.0 µg/m³ | – |
| 10 Aug 2026 | 184102.0 µg/m³ | North-western United States and Canada, 4 to 22 August 2026 |
| 6 Aug 2026 | 18096.6 µg/m³ | North-western United States and Canada, 4 to 22 August 2026 |
| 8 Aug 2026 | 18096.5 µg/m³ | North-western United States and Canada, 4 to 22 August 2026 |
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, Castlegar, Canada, 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/ca/castlegar/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.
Castlegar now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-12 19:07 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).