An incoming tropical storm is set to bring in big waves for the Olympic Games surfing competition at Tsurigasaki Beach in Ichinomia town.

"Well, we haven't had waves for a long time, but this typhoon has increased the size of the waves, and it will go up more on Tuesday, so I hope the surfers can enjoy riding the good waves," said a local on Sunday at Kujukuri coastline as the competition kicked off at Tsurigasaki Beach.

Games organisers have been eyeing tropical storm Nepartak with concern while surfers have welcomed the possibility of some big games.