July in Dessau-Roßlau is the warmest month of the year. In July, the weather in Dessau-Roßlau is typically warm. Average daily high temperature in July is about 23 degrees above zero. On average, Dessau-Roßlau has 12 rainy, 9 sunny, 9 partly cloudy, and 1 cloudy day in July. The rains are usually moderate.