A surge of moist air flowing towards a front is causing highly unstable atmospheric conditions across eastern Japan, particularly in the Kanto, Koshinetsu, and Tohoku regions. Tokyo and its surrounding areas are experiencing extremely heavy, localized rainfall. The Japan Meteorological Agency has issued a “Level 4 Heavy Rain Danger Alert” for parts of Tokyo’s 23 wards, the highest alert level. Residents are urged to be extremely cautious of potential flooding in low-lying areas and underground facilities, as well as rising river levels. Authorities emphasize the seriousness of the situation and are advising residents to take immediate safety precautions. The unstable weather pattern is expected to continue, posing an ongoing risk of further localized downpours.