Predicting Japan cherry blossom season is a challenge
Blooms begin as early as March and late as May in some parts ■
Tokyo, Feb. 11: As spring approaches in Japan, the country's weather forecasters face one of their biggest missions of the year: predicting exactly when the famed cherry blossoms will bloom.
Japan's sakura or cherry blossom season is feverishly anticipated by locals and visitors alike. Many tourists plan their entire trips around the blooms, and Japanese flock to parks in their millions to enjoy the seasonal spectacle.
"People pay more attention to the cherry blossom season than any other flower in Japan," Ryo Dojo, an official of the statistics unit at the Japan Meteorological Agency, told AFP.
The most basic element of predicting when the delicate pink and white petals will begin to unfurl is a large data set of temperatures.
That's because the flowers will come earlier if temperatures rise quickly in spring, Dojo said.
Conversely, if temperatures in the autumn and winter period are higher than usual, the blooms can end up being delayed.
Extreme weather can affect the trees too, with unusual patterns in 2018 prompting some blossoms to appear in October, well before the usual season.
In general, blooms begin as early as March in southern Kyushu and appear as late as May in northernmost Hokkaido.
In a bid to improve its forecasts, some outfits have started crowdsourcing data, including Weathernews, a firm in Chiba near Tokyo.
It relies on photos of buds sent in regularly by 10,000 citizens across the country who are registered on the company's website and app.
"Cherry blossom forecasting is impossible for us without this system," spokeswoman Miku Toma said.