Wildfire smoke can travel thousands of kilometres on the wind
You do not need to be near a wildfire to be affected by its smoke. Health Canada notes that wildfire smoke may be carried thousands of kilometres...
You do not need to be near a wildfire to be affected by its smoke. Health Canada notes that wildfire smoke may be carried thousands of kilometres from the fire zone, which is why fires in northern BC or Alberta routinely degrade air quality in Ontario, Quebec and the eastern United States. The plume rises high into the atmosphere on heat from the fire, then drifts on prevailing winds. Whether smoke comes down to ground level depends on local weather: stable, sinking air pulls smoke down where people breathe it; rising air keeps the plume aloft. That is why a city can wake up to clear blue skies one day and orange haze the next, even when the fire is unchanged hundreds of kilometres away. Check the AQHI (or the AirNow AQI at airnow.gov in the US) for your community, along with the smoke-forecast maps from Environment and Climate Change Canada, BlueSky Canada, or the US Fire and Smoke Map. Smoke forecasts are updated several times a day and can give 24-48 hours of warning that an air-quality event is coming, which is enough lead time to plan indoor activities, run the HEPA cleaner, and pre-fill prescriptions.
Northern BC wildfire smoke regularly turns the sky orange in Toronto and New York — plumes can travel thousands of kilometres before settling to ground level.
Source: Canada — Wildfire Smoke and Your Health
Last reviewed 2026-05-02.
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