Although strong storms to develop in Tahiti during the stormy season which can seem like a cyclone is happening it's not actually a cyclone.
Tahiti does not get any cyclones or hurricanes even though they do get some severe storms that can seem like it.
So you're safe to go to Tahiti even during the stormy season but your vacation won't be as good as it would if you wait until the stormy season is over.
The months November through April are pretty humid and rainy and sometime stormy in Tahiti so it's best to avoid Tahiti during those months.
Any other months are best for visiting Tahiti when it's less rainy and humid but you won't get any cyclones.