
In its weather forecast issued at 6am on Wednesday, the department said the rains would be unleashed by a low pressure area that covers the upper part of the Bay of Bengal, and the strong southwest monsoon prevailing over the Andaman Sea.
It warned residents of Chon Buri, Rayong, Chanthaburi, Trat, Ranong, Phang Nga, Phuket and Krabi provinces to prepare for heavy downpour.
It added that strong waves were likely in the Andaman Sea and the upper Gulf with waves 2-3 metres high in the Andaman Sea.