People won’t know where the message comes from, they’ll just hear your voice as though you were standing next to them. Everyone hears it at the same time. The message is not translated into anyone’s native language, everyone hears it exactly as you say it. The maximum length is 6 of your breaths.
I think I’ll say “I am the Lord your god. You guys are sure fucking the climate up. You’d better lynch those oil executives and have a communist revolution before I send a big fire. I promised no floods, fires are still game.”