Hawaii averages fewer than 1 tornado per year - the rarest of all 50 states. Tropical Pacific climate, island geography, and lack of continental air masses make tornadoes essentially non-existent. Waterspouts are more common than land tornadoes.
Hawaii's stable tropical climate doesn't produce tornado-favorable conditions.
Small islands don't provide continental air masses needed for tornado formation.
Surrounded by ocean. No dry land air convergence.
Trade winds and stable weather patterns don't produce severe convection.
Occasional winter storm events can produce weak tornadoes or waterspouts.
Ocean waterspouts occur more commonly than land tornadoes.
Hurricanes affecting Hawaii can spawn very rare tornado-like events.