TOKYO — A powerful typhoon struck Japan’s main island on Wednesday, stranding thousands of commuters in Tokyo and poured heavy rain on the stricken Fukushima Daiichi nuclear plant in the nation’s tsunami-ravaged northeast.

Evacuation advisories went out to more than one million people across the main island of Honshu as torrential downpours caused flash floods in low-lying areas. As of Wednesday evening, six people had been found dead and seven others were missing, according to Japan’s national broadcaster, NHK.

The storm, called Typhoon Roke, directly hit greater Tokyo, briefly shutting down Japan’s commercial and political center. Strong winds and rains brought most subways and commuter trains to at least a temporary halt, stranding tens of thousands at stations. Bullet train and airline service was canceled.