From the meteorological point of view the climate of Thailand can be divided into three           seasons as follows:

          1. Rainy or southern west monsoon season (mid-May to mid-October). The southern west monsoon prevails over Thailand and abundant rain occurs over the country. The wettest period of the year is from August to September. The exception is found in the Southern Thailand East Coast where abundant rains remain until the end of the year, which is the beginning period of the northern east monsoon and November is the wettest month.

          2. Winter or northern east monsoon season (mid-October to mid-February). This is the mild period of the year with quite cool weather in December and January in upper Thailand but there is a great amount of rainfall in Southern Thailand East Coast, especially from October to November.

          3. Summer or pre-monsoon season, mid-February to mid-May. This is the transitional period from the northern east to southern west monsoons. The weather becomes warmer, especially in upper Thailand. April is the hottest month.