Hi Zaru-Soba,
I usually sail at Kemigawa beach weekends.
Kemigawa beach is close to Odaiba.
Both beachs are familiar to windsurfer in this area.
I found the map someone has made.
You could check where beach is.
http://www.interq.or.jp/blue/lagoon/indexe.htmSo,
If typhoon goes through sea of japan,
We could have fun with strong wind at Odaiba.
It'll be safety, if you have enough skill.
However,
Odaiba is difficult to pridict wind.
Wind doesn't stay constant.
Because Odaiba is almost surrounded by architecture, like building , birdge.
FYI,
The most famous beach in japan is Omaezaki as for wave.
Freestyle is popular at Lake Motosu.
masaya