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Tap any fire or hot spot on the map for its name and perimeter.
≈ EPA AQI for total fine-particle air (PM2.5): wildfire smoke, dust, and typical pollution from traffic and industry, combined, from NOAA's smoke model plus Environment and Climate Change Canada's air-quality model. A modeled forecast, not an official AQI reading.
The model works on a grid about 3 km across, so zooming in shows more map, not more model. A reading is for the neighbourhood, not a single address.
Total-column smoke (mg/m²): how much haze is overhead in the whole air column. High values dim the sun even when surface air stays breathable.
Hot spots (via satellite)
Heat detections from the past 24 hours, which may be where the smoke is coming from. Includes prescribed and agricultural burns, not just wildfires.
Fires likely producing smoke
Named wildfires still burning and over 100 acres. Satellites miss smouldering fires, so these can matter even where there is no hot spot. A mostly contained fire often puts out more fine smoke per acre than a fresh one.
Contained or small fires
Named fires that are fully contained, or under 100 acres. Real fires, but unlikely to be what you are breathing.
Always show current ozone
Ozone is a separate pollutant from smoke. It is not emitted by anything: sunlight cooks it out of traffic and industrial exhaust, so it builds through a hot afternoon and collapses overnight. That is why the official air quality number you see elsewhere can be higher than SmokeCast's on a hot day. The official AQI is the worst of all pollutants, and on those days ozone is the worst one.
SmokeCast always tells you when ozone is in a worse category than smoke and particles, and always shows it when you tap a reading. Switch this on to see it on every reading instead.
This is a measurement, never a forecast, so it disappears when you scrub to another hour. EPA reports it as an eight-hour average, so on a fast-rising afternoon the air can be worse than the number.
Smoke overlay
The coloured layer is total fine-particle air quality (≈AQI): wildfire smoke, dust, and typical pollution from traffic and industry, combined. Clean air shows no colour at all. Turn it off to see the shaded relief map underneath, which is useful when you are placing a custom pin. Tap and hold the map to drop one.
Your favorites on the map
Mark each of your saved places on the map with a coloured dot, so you can see how all of them look at once. The dot follows the hour you’re looking at, so it changes as you scrub through the forecast.
Which way I’m facing
Add a compass beam to the blue dot so you can tell which direction you’re looking.
This bar is a chart. Its colors show your location’s air quality for the next 72 hours (hour by hour). Green = good air, yellow and up = worse. Drag the white dot or press play.
Tap a fire or hot spot for its name, size, perimeter, and containment. Tap and hold anywhere else on the map to drop a pin: a trailhead, campsite, etc.
Wildfire smoke, dust, and everyday pollution, combined into an approx. fine-particle AQI at breathing level. SmokeCast corrects it with live EPA readings.
— is our guess from your connection.