Average 60-80 feet. Tends to be a bit better during winter months.
71-72 winter. 80-81 during summer months.
Currents are variable and change by the day. Some dive sites such as Niihau can experience fairly strong currents where drift diving is done.
Best Months For Diving:
In the winter the visibility tends to be a bit better. Visibility during any months will be affected by rains. After heavy rains it can be as low as 30 feet. On nice days it can be as much as 100 feet. Visibility on Niihau tends to be better than around Kauai.