I like lightning.
It has power. Bolts can raise the temperature of the air around it 50,000°F, dealing a mass expansion and massive boom -- thunder.
Thunderstorms are in my top list of natural phenomena.
Cumulonimbus clouds are what "make" thunderstorms. At least in the summertime, they do. See that tower of cloud? That's got crazy currents in it. What happens when water gets flung upward into the atmosphere? It turns to ice, dummy. The ice doesn't stand a chance against the currents, though, so they still get tossed around.
And the ice bumps into other ice, and the charges change. Positive goes up, and negative goes down. The separation makes the particles seek each other out.
Think of one ice particle as a wool sock, and another as a shag carpet. Everyone knows that you can zap your mom when you slide your feet on the carpet. Your body is like the cumulonimbus as a whole, and when your finger (the bottom of the cloud) gets close to your mom's arm (the ground) the charges release in a spark (or a devastating blast of electrical energy only 30 microseconds long).
There's always a little "click" sound when you get close enough to yer mum's arm. I suppose you could say that's the spark heating up the air and making it expand? I dunno. In any case, a full-fledged bolt of lightning heats it up more, faster, and in huge quantities.
Then.... Boom. (It's a link. Click on it.)
Not much is more fascinating and terrifying (at the same) than a crackling explosion of thunder.
I live for it.