In August, the weather in Aix-en-Provence is typically hot. Average daily high temperature in August is about 29 degrees above zero. On average, Aix-en-Provence has 19 sunny, 8 partly cloudy, and 4 rainy days in August. The rains are usually light. August as well as June, July, and September is considered the most comfortable time to visit Aix-en-Provence.