The answer to this question depends on what part of Germany you are visiting. In general, the further north you go, the colder the weather will be. For example, Berlin is located in the northern part of Germany and the average temperature in May is 14 degrees Celsius. On the other hand, Munich, which is located in the southern part of Germany, has an average temperature of 19 degrees Celsius in May. So, if you're looking to escape the cold weather, you might want to consider visiting southern Germany during the month of May.