A southerly wind and high cloud caused the spectacular lightning show, minus the thunder, across the Bay of Plenty last night.
Rotorua residents took to social media with video and photos of the unusual display around 8.30pm.
Meteorologist Tui McInnes said there were 25 strikes in the Bay of Plenty region, and all but one were in the eastern ranges.
There were 28 in the Taupō region around midnight.