Schoolchildren waded through floods as forecasters warned of heavy rainfall across Thailand.

Footage shows the pupils walking across the swamped Phimai-Chum Phuang road in front of the Phimaidamrong Wittayakhom School in Nakhon Ratchasima province, on July 10.

Authorities said the rain covered the streets in up to 12 inches of flood, with the school ending classes later than usual to let the water subside.

The Thai Meteorological Department said the southwest monsoon will cover Thailand, the Andaman Sea, and the Gulf of Thailand.

A low-pressure area over northern Vietnam was also creating stormy conditions.

Locals were advised to prepare for possible flash floods and mountain runoff, especially in low-lying areas.

Thailand and neighbouring countries in Southeast Asia are in their annual monsoon rainy season which sees soaring temperatures followed by powerful rain storms in the afternoon leading to widespread flash floods.