August in Merignac is the sunniest and the warmest month of the year. In August, the weather in Merignac is typically warm. Average daily high temperature in August is about 25 degrees above zero. On average, Merignac has 20 sunny, 9 partly cloudy, and 2 rainy days in August. The rains are usually light. August as well as July is considered the most comfortable time to visit Merignac.