wildfiresmoke.ca independently compares live Canadian air-quality measurements against the two operational wildfire-smoke forecast models — every hour, at every station. Forecast pages and maps exist elsewhere; the point here is showing observations and both models side by side so you can judge how much to trust the forecast where you live.
Hourly PM2.5 from 260 federal, provincial and territorial regulatory monitors, aggregated via the AirNow data exchange and supplemented directly from provincial feeds (Ontario, Manitoba, British Columbia, Alberta, Québec's RSQAQ). Real-time data is not final-verified: agencies may correct values later. Timestamps mark the end of each measurement hour, matching provincial displays.
Both are sampled at the grid cell nearest each station (and each city page's coordinates). The models are independent and frequently disagree; disagreement itself is useful information. The map can optionally drape and animate FireWork's wildfire smoke plume — the PM2.5-WildfireSmokePlume field, the fires' contribution only, so clean-air regions stay blank — as a coloured surface (next-48-hour maximum plus a 3-hourly animation). ECCC open data, reproduced with attribution (see also ECCC's own FireWork maps); FireSmoke's terms do not permit the equivalent overlay. Everything else on this site remains total PM2.5.
The map can animate 10-metre surface wind from ECCC's Regional Deterministic Prediction System (RDPS, ~10 km grid), sampled for the current hour and resampled to a regular grid; flowing particles are drawn with leaflet-velocity (CSIRO). Because the model publishes wind components relative to its rotated grid, this site derives true-north components from the published speed and direction instead. Surface wind indicates near-ground drift — smoke frequently travels at higher altitudes on different headings, so treat it as context, not a plume trajectory.
NowCast is the US EPA's smoke-responsive weighted average of recent hourly readings; the coloured chart bands are US EPA AQI category thresholds (24-hour basis, 2024 revision) and apply to NowCast, not single hours. AQHI values and forecasts are Environment Canada's official published numbers, never computed here. Québec's IQA is shown for Québec stations.
The map offers an optional layer of low-cost community sensors, Powered by PurpleAir. Raw readings are corrected with the US EPA equation (Barkjohn et al. 2021, with its high-concentration smoke extension) before display, and only sensors adding coverage are shown: anything within 25 km of a regulatory monitor is hidden, and the rest is thinned to roughly one sensor per 10 km. These are not regulatory monitors — they never enter the verification statistics or the AI-written outlook, which use official federal, provincial and territorial data only. Each sensor is assigned to its province, which supplies the timezone its forecast times are displayed in. On the forecast map view, sensor dots are coloured by the modelled 48-hour maximum sampled at the sensor's location (higher of FireSmoke and FireWork, exactly as for stations), and a red outline marks sensors whose current corrected reading exceeds both models by the same thresholds as the station halo. Popups include an approximate index value matching provincial practice — the IQA PM2.5 sub-index inside Québec (which reports no AQHI; on the AQHI view Québec sensors get the same neutral marking as official Québec stations), AQHI+ (the PM2.5-only smoke amendment used by British Columbia and Alberta) elsewhere — always labeled as estimates; the IQA view shows only sensors within Québec. AQHI and IQA values shown for official stations remain the agencies' published numbers.
The map can also show the locations of currently active wildfires (out of control, being held, or under control) from the Canadian Wildland Fire Information System, Natural Resources Canada, refreshed hourly. Markers show location and agency-reported status and size only; fire perimeters and out fires are not displayed.
Every hour, each model's earlier forecasts are matched against what stations actually measured, and the errors are logged per station, per model and per forecast run. The AI-written national outlook draws only on these measured values and model outputs — it is generated from structured facts, validated, and clearly labeled.
Observations, indices and pages refresh hourly. Model runs arrive on their own schedules (FireSmoke 4×/day, FireWork 2×/day); the freshness panel on the dashboard shows the age of every input.
Independently built and hosted in Canada (Toronto). Source data belongs to the agencies above. Questions, corrections or data issues: contact@wildfiresmoke.ca. Site last generated Aug 06, 2026, 1:25PM.