BANGKOK, Oct. 18 -- Thai authorities have warned of possible flash floods and landslides across Bangkok and 35 provinces as heavy to very heavy rain threatens large parts of the country until October 25.

The Thai Meteorological Department said the wet weather would initially affect southern and eastern Thailand before spreading to Bangkok, central Thailand and other regions from October 21 to 25.

The warning comes as Thailand's Department of Disaster Prevention and Mitigation (DDPM) placed 35 provinces and the capital on alert, with local authorities instructed to prepare emergency response teams and equipment, according to The Nation.

Persistent rainfall is forecast in the south and east from October 18 to 20, with some areas expected...