It will rain heavily in the western part of the Central Plains while rain will continue and then start to decline in Greater Bangkok and the East on Sunday, according to the Meteorological Department.
Director-general Sugunyanee Yavinchan said a low-pressure cell remains over the western part of the Central Plains and the rather strong southwest monsoon reigns over the Andaman Sea, the South and the Gulf of Thailand.
She warned people to avoid low-lying areas and flood-prone roads, which could be inundated temporarily.
Small boats should remain ashore in the upper part of the Gulf of Thailand and the Andaman Sea until Monday.
From Monday to Friday, rainfall will decline in Thailand. However, there will be isolated heavy rain in the western part of the North and the Central Plains as the active low-pressure cell moves to Myanmar.