What drives haze
Why the air gets better or worse.
Rain, wind, humidity and the time of day all move PM2.5 up or down. Pick a situation or drag the sliders, and the 3-hour forecast model shows which of them pushed its forecast up and which pulled it down.
Try a situation
Atmospheric Variables
18 µg/m³
Normal clean air is 5–15 µg/m³; hazy episodes exceed 55 µg/m³.28 µg/m³
0 mm
Rain acts as a natural air filter, washing smoke particles out of the sky.22 km/h
Light winds (< 8 km/h) allow smoke to accumulate; strong winds disperse it.58%
High humidity causes moisture to bind to smoke particles, worsening haze visibility.32 °C