Period to visit Japan

Typhoon in September
I am deciding on the period to visit Tokyo between end of August or end of September. Which is the better period considering the weather and the chance of Typhoon and other factors. Please give some opinions. Thanks a lot

http://www.japan-guide.com/forum/quereadisplay.html?0+38733

There is not a big difference in terms of risk of typhoon.

The main differences are temperatures and chance of rain:

The daytime high average in late August is 30 degrees. In late September it is 24 degrees.

Late August tends to be considerably sunnier than late September. According to the weather statistics, sunny days make up more than 50% in late August. But the percentage drops to around 33% in late September.

I think Tokyo is brutal in August - way too hot to enjoy the city. September is hot too but not as bad, and kids are back in school and there are fewer tourists. There are, however, zillions of festivals in August that don't happen at other times of the year. The Samba Festival! How can you miss it!
As far as typhoons go, it's kind of the luck of the draw. Around the Tokyo area they mostly cause rain and maybe some gusty winds, and mostly not even that.