New Supercomputer to Improve Torrential Rainfall Forecasts

The Yomiuri Shimbun

7:00 JST, March 27, 2023

The Japan Meteorological Agency held a press viewing of a new supercomputer for predicting the occurrence of linear precipitation bands that bring intense downpours.

The agency aims to improve the accuracy of forecasts with the latest supercomputer, which has about twice the calculation power of the current model.

The agency currently predicts the amount of rainfall for each five kilometers square of the Japanese archipelago to issue forecasts for the occurrence of linear precipitation bands in such wide-area units as the Tokai and Kinki regions.

With the introduction of the new supercomputer, the agency can narrow the range of rainfall forecasts to every two kilometers square. It plans to start making forecasts for each prefecture in fiscal 2024.

Only three out of 13 forecasts issued by the agency last year for linear precipitation bands were accurate, and the low accuracy rate is a problem.

The new supercomputer, manufactured by Fujitsu Ltd., has been in operation since March 1 in a company facility in Tatebayashi, Gunma Prefecture.