What does 1 Kings 18:44 mean?

The seventh time, the servant came back and said, 'There’s a little cloud, about the size of a man’s hand, coming up from the sea.' Elijah said, 'Go tell Ahab, “Get your chariot ready and head down before the rain stops you.”' 1 Kings 18:44 - Modern Text Bible

(Finally, a small cloud appears. Elijah knows this is the start of the downpour and warns Ahab to hurry before the rain makes travel impossible.)