SmokeDarSaint Louis wildfire smoke and air quality
Live readings for Saint Louis, Missouri: whether wildfire smoke is overhead, what the surface air measures, and how the next five days look. Free, no signup, no ads.
How smoke reaches Saint Louis
Saint Louis is among the last stops for Canadian smoke, which arrives old, high, and diluted, and it also catches Western US smoke on the westerlies. The bigger local risk is stagnation: hot, still spells that let any arriving haze pile onto the metro's own summer particle load. That is why SmokeDar reports two numbers for Saint Louis: smoke aloft (modeled aerosol optical depth from Copernicus CAMS) and surface air (PM2.5 and US AQI, observed AirNow monitor data when a monitor is nearby). They are different things, and they often disagree.
Saint Louis right now
–US AQI
Open the live radar for the current reading.
Open the live Saint Louis radarWhat the numbers mean
AQI 0–50 is good and 51–100 is moderate; ordinary days. From 101–150, sensitive groups (kids, older adults, pregnant people, anyone with heart or lung conditions) should shorten hard outdoor exercise. Above 150, everyone should cut both time and intensity outdoors. The full playbook is in the Smoke Guide.