The Meteorological Department forecast is for more heavy rain nationwide into Tuesday.
Chomparee Chompurat, director-general, said on Monday that a monsoon trough over the North and the Northeast and the strong monsoon over the Andaman Sea and the Gulf of Thailand would bring heavy rain nationwide.
She advised people be ready for possible runnoff from high terrain, and small boats should be kept ashore because seas would be rough.
From Wednesday to Saturday the monsoon trough would move to Myanmar and upper Laos and the monsoon would be weaker over the Andaman Sea and the Gulf of Thailand. Heavy rains would continue in the North, the Northeast and the East.