Japan’s Nagano Prefecture experienced record-breaking rainfall in a short period, prompting a severe weather alert. The intense downpour, concentrated near Ina City, triggered a “Record Short-Time Heavy Rain” meteorological disaster early warning. A Level 4 danger warning – the highest level – is in effect for parts of Nagano Prefecture, indicating a high risk of flooding in low-lying areas and landslides. The heavy rain is attributed to moist air impacting eastern and central Japan, including the Kanto-Koshin and Tokai regions. Residents are strongly advised to take maximum precautions against potential disasters. Alerts are also in effect for a wider area stretching from northeastern to southwestern Japan due to atmospheric instability.