Approaching from the Pacific Ocean, Typhoon Lan made landfall on Tuesday at the southern tip of Wakayama prefecture, some 400 kilometres southwest of Tokyo.
The typhoon, which followed closely on the heels of Typhoon Khanun during Japan's peak Obon holiday season, lashed wide swathes of central and western Japan with heavy rains and powerful winds.
Power outages hit more than 21,000 households in central Mie prefecture, and thousands more in nearby prefectures, including Osaka, public broadcaster NHK said.
Anticipating the dangerous levels of winds and rains a day earlier, high-speed train operators had also planned suspensions of services affecting the area. Convenience store operator 7-Eleven closed more than a 100 stores.
Over the next 24 hours, the central Tokai region - home of Toyota Motor - was expected to get about 350 millimetres of rainfall, nearly three times the average rainfall for August.
Many factories close during the Obon holidays, when city-dwellers return to their ancestral homes.
Typhoon Lan had sustained winds of 150km/h and was moving northwest across the western part of the main island of Honshu. It was forecast to reach the Sea of Japan by early on Wednesday and continue north along the sea, according to Japan's weather agency.
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