The typhoon is forecast to have an atmospheric pressure of 935 hectopascals at its centre, and sustained winds of up to 234 kilometres per hour (145 miles per hour) by Monday, the meteorological agency said.
The cargo ship sent a distress call from the west of Amami Oshima island in southwestern Japan on Wednesday as the region experienced strong winds, heavy seas and torrential rain from Typhoon Maysak as it headed towards the Korean Peninsula.