The warning, issued by TMD Director-General Wanchai Sakudomchai, was first issued at 5am.
“During 16-20 June 2018, the stronger southwest monsoon prevails over Thailand, the Andaman Sea and the Gulf will intensify,” the warning read.
“The strong wind and waves in the Andaman Sea and the Gulf of Thailand. The waves height are likely 2-4 meters in the Andaman Sea and the upper Gulf of Thailand from Surat Thani upward about 2-3 meters,” it added.
All ships should proceed with caution, and small boats in the Andaman Sea and the upper Gulf keep ashore, TMD Director-General Wanchai urged.
“People along the coast of the East and the South west coast should beware of inshore surges,” he added.