Typhoon Man-yi has hit central Japan as officials issued a "special warning" of heavy rain, amid fears the storm could go on to hit the crippled Fukushima nuclear plant.

The typhoon is generating heavy rain and wind gusts of more than 140 kilometres per hour.

It is tracking north-east along the main Japanese island of Honshu at a speed of 45 kilometres per hour and was expected to pass over Fukushima this afternoon.

TEPCO workers at the plant are battening down the site as the typhoon approaches.