The latest typhoon to hit southern Japan struck on Monday, bringing heavy rains. Officials warned of floods and strong winds that could go on to hit the damaged Fukushima nuclear plant.
Around 200 domestic flights scheduled for Monday were cancelled. Most of the affected flights were those leaving Tokyo; train services were also reduced.
The storm was carrying winds up to 144 kilometres (90 miles) per hour overnight Sunday and was moving in a north-northwesterly direction. The Japan Meteorological Agency said.
It would probably hit southern parts of the main island Honshu on Monday morning, possibly around 9:00 am (0000 GMT) in Shizuoka prefecture, southwest of Tokyo.
The typhoon was then expected to head northeast towards Tokyo and its surrounding region by around noon and cross the northeast including the Fukushima area, according to its predicted track.
At Fukushima, workmen have struggled night and day to contain leakages from the nuclear plant after the March 11, 2011 earthquake and tsunami. This led to the contamination of groundwater by radioactive materials flowing into the Pacific Ocean.
With even more torrential rain expected on Monday, the fear is that contaminated water will seep into the groundwater. Workers frantically pumped water from around highly radioactive tanks at the plant to lower the risk.
The typhoon had already brought heavy rain and strong winds in the south and east before even hitting Japan but no major damage was reported. The weather agency has now issued flood warnings and forecasts that the heavy rain will cause mudslides and high ocean waves to many areas along the Pacific coast.
Officials hope that the latest Japan typhoon will not further complicate the work at the Fukashima plan.