September in Oaxaca de Juárez is the rainiest and the cloudiest month of the year. In September, the weather in Oaxaca de Juárez is typically warm. Average daily high temperature in September is about 22 degrees above zero. On average, Oaxaca de Juárez has 23 rainy, 5 partly cloudy, 1 sunny, and 1 cloudy day in September. The rains are usually heavy. September as well as June, July, and August is considered the most uncomfortable time to visit Oaxaca de Juárez.