An area of low pressure over the central South China Sea has developed into a tropical depression that's expected to hit Thailand on July 25-26, the Meteorological Department said in its 5am announcement on Sunday.
The storm is moving slowly in a westerly direction. It is expected to reach the coast of Vietnam today and tomorrow.
People are advised to monitor weather reports.
With a monsoon trough lying across Myanmar, Laos and Vietnam, and the moderate southwest monsoon prevailing over the Andaman Sea and Thailand, frequent thundershowers and isolated heavy rain are expected, especially in the North, the Northeast and the East.
Moderate winds in the upper Andaman Sea will bring waves reach about 2 metres, the bulletin continued. People should beware of severe weather conditions, and all vessels are advised to proceed with caution.