SmogRank / Canada / Quebec / Brossard

Brossard, month by month

Brossard has a measured daily mean on 1,265 days since 1 January 2023. Its worst month was June 2023, at 66 US AQI (17.3 µg/m³), 326th of 1,603 cities on that month's world ranking. Its cleanest was April 2024, at 18 US AQI (3.3 µg/m³). 2025 averaged 39 US AQI (7.1 µg/m³), against 36 US AQI (6.4 µg/m³) in 2024.

Every month since 2023

Each square is a month's mean PM2.5 in US AQI from Brossard's measured days, with its place on that month's world ranking under it. A month has a mean once 70% of its days are measured, the rule the monthly rankings use; under that, the square gives the days measured. Each square opens that month's ranking with Brossard marked; each year, the year's. A dashed square is the running month, so far.
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

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
MonthWhy
Aug 202521 of 31 days measured; a month needs 22. The others: 10 with under 18 hours of readings or readings that failed our checks.
Mar 202311 of 31 days measured; a month needs 22. The others: 20 missing from OpenAQ's archive.
Feb 20233 of 28 days measured; a month needs 20. The others: 25 missing from OpenAQ's archive.

A day counts once 18 hours of it are measured; a month needs 70% of its days.

Brossard's worst months

MonthUS AQIDays measuredWorld rankEpisode
June 2023 6617.3 µg/m³30 of 30326thof 1,603Eastern United States and Canada, June and July 2023
United States and Canada, June 2023and 1 more
July 2025 6114.7 µg/m³31 of 31433rdof 2,889North-eastern United States and Canada, 29 July to 9 August 2025
North-eastern United States and Canada, 24 to 28 July 2025and 1 more
July 2023 5812.9 µg/m³30 of 31294thof 1,432United States and Canada, July 2023
Eastern United States and Canada, June and July 2023
June 2025 5511.3 µg/m³30 of 30938thof 2,508Northern United States and Canada, May and June 2025
July 2026 5410.8 µg/m³31 of 311,165thof 2,784–
September 2023 5310.3 µg/m³30 of 30540thof 2,176North-eastern United States and Canada, September and October 2023

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.

Brossard's worst days

DayUS AQIEpisode
25 Jun 2023 214138.5 µg/m³Eastern United States and Canada, June and July 2023
26 Jul 2025 16270.6 µg/m³North-eastern United States and Canada, 24 to 28 July 2025
26 Jun 2023 14955.1 µg/m³Eastern United States and Canada, June and July 2023
6 Jun 2025 14955.1 µg/m³Northern United States and Canada, May and June 2025
1 Jul 2023 12946.7 µg/m³Eastern United States and Canada, June and July 2023
27 Dec 2024 11139.6 µg/m³South-eastern Canada and United States, December 2024
15 Jul 2025 11039.1 µg/m³Northern United States and Canada, July 2025
3 Aug 2025 10637.7 µg/m³North-eastern United States and Canada, 29 July to 9 August 2025
26 Dec 2024 10537.2 µg/m³South-eastern Canada and United States, December 2024
30 Jun 2023 10336.5 µg/m³Eastern 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, Brossard, Canada, 1 Jan 2023 – 9 Oct 2026. Monitor data from AirNow, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/ca/brossard/history (accessed 12 Oct 2026).

Download chart (PNG)

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.

Brossard now: the last 24 hours, its ranks today and the last 12 months day by day.

Updated 2026-10-12 17:07 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).