What this has in common with the megaflashes is that both are flashes between the clouds, which don't necessarily hit the ground: > Megaflashes crawl through t

What this has in common with the megaflashes is that both are flashes between the clouds, which don't necessarily hit the ground: > Megaflashes crawl through the clouds but can produce or induce ground connections at various points. I have seen a few thunderstorms like you describe (although probably less powerful) at night where I live. Lots of very frequent flashes, but only between the clouds and with almost no thunder.