Most years, the typhoon season peaks in September, as illustrated by the recent Typhoon No. 9, called Fitow, which killed two, and Typhoon No. 11, also known as Nari, which approached Okinawa last week.

The seasonal turbulence remains a threat to Japan despite improvements in meteorological satellites and weather forecasting technology — and some experts theorize that global warming may have altered its characteristics.

Following is some basic information on typhoons: