A video headline and an official impact record
Our video describes widespread Japanese flood alerts. Japan's Ministry of Land, Infrastructure, Transport and Tourism has published successive reports on the impacts of Typhoon 24 and frontal rain, with an update dated 11 September. Those reports are a better place to check affected roads, rivers and infrastructure than a static video headline. The video's “2+ million” wording should not be interpreted as the number who physically left their homes: a notice's population, actual departures and people sheltering are distinct measures.
Alerts are local and time-sensitive
Japanese evacuation instructions are issued by local authorities and can change as rainfall, rivers and landslide risk evolve. A national article cannot substitute for the municipality's current instruction. Even after rain weakens, saturated ground and swollen rivers can keep a hazard active.
The linked ministry page contains dated PDFs, so readers should open the report for the exact time they want to compare. This companion records what the video discusses and points to the official record; it does not assert a fresh nationwide evacuation total for 15 September.