What does Jeremiah 46:18 mean?

As surely as I live, says the King—whose name is the Lord of everything—someone as powerful as Mount Tabor among the hills, or Mount Carmel by the sea, is coming. Jeremiah 46:18 - Modern Text Bible

(God swears by his own name that a mighty conqueror is coming, someone as unmissable and unstoppable as the great mountains.)