I didn't have the patience to do too much Google research, as weather references are buried in a gazillion references to the song (and I live with dialup), but I found a few obscure references to 'smokestack lightning', one of which described lightning over mountains adjacent to grasslands, another lightning associated with volcanos, and a third about lightning associated with, er, smokestacks, and an odd one where the term was used to describe lightning from a Tesla generator.

So maybe nobody learned the song wrong, and the verse alludes to leaving a smokestack filled factory town.