NHK has learned that according to a study, a major river that runs through Tokyo and neighboring Saitama Prefecture could have breached its banks if Typhoon Hagibis had brought more rain last year.
Tokyo University of Science Professor Nihei Yasuo conducted a flood simulation on the Arakawa River using 21 forecasts the Meteorological Agency issued 10 hours before the typhoon made landfall in October last year.
Japanese financial institutions are offering support for victims of the heavy rains that have battered southwestern and central Japan. Four major banks say they will lend money at reduced interest rates to people who need their homes rebuilt or renovated.
The banks are Sumitomo Mitsui, Mitsubishi UFJ, Mizuho, and Resona.
Customers of an online bank and three regional banks have had problems using their services on Sunday.
SBI Sumishin Net Bank said most of its online banking functions stopped working around 10 a.m. on Sunday.
Banks across Japan are buying trucks fitted with ATMs so that customers can withdraw cash in the event of a massive natural disaster.
The vehicles were sent to areas hit by a major earthquake in northern Japan last June, and areas flooded by Typhoon Hagibis last October.