An entire house collapsed after flash floods eroded its foundation during the onset of the annual rainy season in Thailand.

Footage taken in Lampang province in the north of the country on May 17 shows the two-storey house standing on unstable wooden columns which began snapping as they tilted due to the strong currents.

Homeowner Somthat Kankaew filmed the moment the damaged supports gave way, causing her house to be flattened within seconds.

Somthat said she had left her home and stayed with her relatives nearby fearing for her safety when the floods swept through their village. No one was inside the structure when it collapsed.

Local government officials, police officers, and volunteers later helped clean up the area and assisted other families stricken by the flood.

Thailand's Meteorological Department said the country officially entered its rainy season on May 13. Bouts of rain showers are expected to occur until mid-October, with a dry spell possibly occurring from mid-June to mid-July due to the El Nino and La Nina phenomena.

Thailand and other countries in Southeast Asia such as Malaysia, Indonesia and the Philippines are at the start of their tropical monsoon rainy season, which last until late November.

Soaring temperatures reaching 35 degrees Celsius are often followed by powerful tropical storms with thunder, lightning, rain and flash floods which cause rivers to flow faster and become dangerous.

Many of the under-developed nations struggle to cope with the heavy rain due to under-investment infrastructure.