Rainfall across much of Thailand starts to peak with Chiang Mai and the north usually receiving its heaviest rainfall of the year. Temperatures continue to fall although humidity will remain high (avg temp: 26 - 30 °C).
Conditions on the beaches and islands of the Thai peninsular will vary. The west side of the peninsular is receiving its heaviest rainfall of the year (avg temp: 27 °C) whilst on the east whilst there will be rainfall, although early in the month this will be far lower (avg temp: 27 °C).
As September approaches the rainfall will increase with Hua Hin and nearby beaches usually providing the best of the beach conditions across the country.