According to Makoto Shinkai, the film's central theme is loneliness. This was inspired by the Man'yoshu, Japan's oldest collection of poems; in that volume, love was represented by the word "koi", or "lonely sadness"; more accurately, a longing for someone in solitude. Shinkai described the film as a love story towards people who feel lonely or incomplete in their social relations, but who don't feel that they need to fix this loneliness.
The character of Yukino has a brief cameo appearance in Your Name. (2016), which was also directed by Makoto Shinkai.
The film was created using a combination of hand-drawn animation, rotoscoping and computer animation (CGI), with the latter facilitating the realistic appearance of the film's rain sequences.
Makoto Shinkai, having lived for ten years in Shinjuku, wished to capture the beauty of the scenery in modern Tokyo and showcase it in a film. He set about taking thousands of photos, upon which he created storyboards for the film.
According to Makoto Shinkai, rain in this film represents the force of love: neither can be controlled or stopped.