The temperature in Germany during the summer is usually warm during the day (75-80 degrees Fahrenheit) and cooler in the evening. Germany can experience relatively cool spells, too (65 degree high during the day). In some summers past it has been very warm and humid so bring along appropriate attire. You should pack a warm sweater for the evening and cool days. Bring clothes that you can layer for ease of comfort. There may be some afternoon rainstorms, so a light rain jacket is essential.