On this page, i will provide you helpful information. Web result if you come to japan in the spring, i would recommend that you prepare both warm and cold weather clothing. It’s recommended to wear a layer of clothing:
Back to school spring outfit ideas
Spring outfits yellow
Spring picture outfit ideas for school
What to Wear in Japan in Spring March, April and May Japan Web Magazine
Web result japan in spring:
In march in japan, you may still feel cold especially in the early morning and evening as it snows in some areas like hokkaido.