Droplets in smoke-affected clouds were too small to stick together and become heavy enough to fall as rain. Researchers suspect less rain may create a dangerous feedback loop where droughts and wildfire cycles worsen with insufficient rainfall to drench the land.

Can smoke clouds make rain?

It does indeed, according to a study she and her colleagues published recently in Geophysical Research Letters: Smoke particles make some clouds denser and more tightly packed with tiny droplets—a combination that means the water in them is less likely to fall as rain.

Does smoking inhibit rain?

Meinrat Andreae of the Max Planck Institute for Chemistry in Mainz, Germany, and colleagues report that a surfeit of smoke particles can delay rainfall, because small droplets form instead of fewer, larger ones. These small droplets don't fall as rain but rise higher up in the atmosphere, releasing energy as they cool.