There are many wonderful things about visiting Japan throughout all the seasons. However, if you happen to be someone who likes warm weather, festivals and fireworks, you will not be disappointed by visiting Japan in summer! Summer in Japan lasts from about June to mid-September. Summers are hot and humid, with temperatures ranging from approximately 70° to 90° Fahrenheit (21° – 32° Celsius).
Andreas Zuleta of Deep Japan has written a helpful article explaining the attractions and activities of Japan in the summer. You will find a number of other insightful articles about Japan in the summer on the Deep Japan website including The Season of Fireworks, and Yatil – Festival Food Stalls.