Why does the air become cleaner after precipitation?

It is no secret that after precipitation in the form of rain, a large amount of ozone remains in the air. This is especially noticeable after a thunderstorm, as it carries a powerful electric charge, thereby ionizing the air. In addition, precipitation serves as an excellent filter that removes fine dust particles from the air. Instead of rain, they settle to the ground, thereby dustiness and concentration of air pollution at this moment is significantly reduced.