thunderstorm

"Thunderstorm" means a weather phenomenon with electrical discharges (lightning) and thunder (though if the storm is distant, you may not hear it). Because these storms have a lot of air turbulence and, usually, a lot of precipitation, we thing of those features as part of a "thunderstorm". But it is the electrical discharges which identify this sort of storm.

You can BE in a thunderstorm or you can see one approaching.

Lightning and its consequence, thunder, are produced by a thunderstorm in progress at that time.

Thanks, centrox.