Heavy rain is forecast to continue in provinces in all regions, including Bangkok, from Saturday into Wednesday, with flash floods and overflows expected in high-risk areas.

The Meteorological Department on Friday said another high-pressure system from China will extend into upper Laos and upper Vietnam between Sept 17 and 21, This will cause a monsoon trough to move down and lie across the North, Central and Northeast of Thailand. The southwest monsoon prevailing over the Andaman Sea and the Gulf of Thailand will strengthen.

These conditions are expected to bring heavy to heavy rain with sometimes strong winds to hit the North, Northeast and Central Plains, including Bangkok and its vicinity, the East and the South.

Residents of those area should make preparations. Accumulated rainwater may cause flash flooding, particularly in low-lying areas.

Waves up to 1-2 metres high are forecast for the upper Andaman Sea and the upper Gulf of Thailand, and more than 2 metres high during thundershowers.