 Anytime you pass a current through the air, lightning, for example, I've talked about the lightning rain burst, if you've ever experienced that during a thunderstorm and there's a lightning strike very close to you and you may or may not have noticed a dramatic increase in the rain rate for a short period of time. Literally, that lightning bolt coalesces the water near it into a column of water that then collapses at a very, very steep rate.