What's the weather like on the cruise ship to Jeju Island in September?

The weather is good in September, but it's best to confirm it one week before coming. Cruise travel is like this. When you arrive at Jeju Island Pier, the bus will pick you up, then take you to eat the cheapest meal, which Koreans don't eat, then take you to the duty-free shop for shopping, and then take you to the pier. The trip is over. Less than 6 hours before and after the trip to Jeju Island, I did nothing, ate the cheapest junk meal, and then visited the duty-free shop. The trip is over.