Is there any way to make Lightning (as in a storm, not Lighting) with the flash and all in GoldSrc/CS? I mean, like what you get when you see a Flashbang go bang.
I am trying to design a creepy castle at night, so if possible, the flash should not be seen when indoors, at least not when not looking outside.
Also related, is there any way to simulate thunder on the sky/clouds? I don't mean the lightning bolt, but rather small sections of the sky going white.