The National Water Resources Office (สทนช.) warns of flash floods, waterlogging and landslides from 22 to 26 September 2026 across the north, central, east and parts of the south. Water released through the Chao Phraya dam may raise levels 0.75-1.25 m in Chai Nat, Sing Buri, Ang Thong, Phra Nakhon Si Ayutthaya and Pathum Thani. Businesses in those provinces and in Bangkok, Nonthaburi and Samut Prakan (Bang Bo) should move stock off the floor, plan alternative delivery routes, and check staff and customer access. Watch official alerts and be ready to evacuate if the situation worsens.