Across Japan, meteorological stations of all prefectures and cities, following national regulations, conduct long-term "biological seasonal observations" for the blooming of plum blossoms, apricot blossoms, cherry blossoms, the reddening of maple leaves and ginkgo leaves, and the chirping days when you can hear birds such as the yellow oriole and the titmouse. They then gather the data at the Japan Meteorological Agency, which connects areas that have the same day of blooming, leaf reddening, or bird chirping on a map with a line, and announces it as the "XX Front."
This event started in 1925 and has nearly seventy years of history in Japan. Among all, the "Sakura Front" is what the public pays the most attention to. Newspapers and television stations actively report on it, starting from Okinawa in mid-to-late January, through the Kanto region in late March, the Northeast region in early April, and finally reaching the northern part of Hokkaido in mid-to-late May.
