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cherry blossom front
The line on weather maps showing the progression of cherry blossom blooming across Japan, moving generally from south to north between late March and mid-May. A widely reported seasonal phenomenon.
Cultural note
The 桜前線 is a uniquely Japanese concept that tracks when cherry blossoms begin to bloom across the country. It typically starts in Okinawa in January and reaches Hokkaido by May. Japanese weather services issue detailed forecasts, and the front's progress is major seasonal news.
The term borrows 前線 (front) from meteorology, treating the blooming pattern like a weather front moving across the country.