According to Nagano Prefecture, due to heavy rain, the Tenryu River exceeded the "flooding danger water level" at the Shimohama Water Level Observatory in Okaya City by 7:40 am, which has a high risk of flooding.
On the other hand, at the Sawando Water Level Observatory in Ina City, the water level fell below the "Flood Dangerous Water Level" by 8:00 am.
In addition, the Sai River, which flows through Nagano City, exceeded the "flooding danger water level" by 7:50 am at the Hirosaki Water Level Observatory in the city.