December in Ayutthaya is the coldest month of the year. In December, the weather in Ayutthaya is typically hot. Average daily high temperature in December is about 29 degrees above zero. On average, Ayutthaya has 18 partly cloudy, 10 sunny, 2 cloudy, and 1 rainy day in December. December as well as January is considered the most comfortable time to visit Ayutthaya.