"Warm air is light and rises up which cause it to become unstable and that's what triggers these thunderstorms."
Yesterday Metservice meteorologist Amy Rossiter said reports of red and orange flashes could be attributed to the way the lightning was reacting to clouds or things in the atmosphere.
— Severe Weather Info (@MetServiceWARN) April 7, 2019
Last night police urged motorists to take extra care in lower Bay of Plenty areas on the route between Turangi and Tokoroa and the route from Taupō to Rotorua.
"The roads are extremely slippery following heavy hail in the area.
Hail settled on a property on Whakakpapa Rd near Taupō. Photo / Supplied
A MetService severe weather watch was in place for eastern parts of the North Island overnight on Sunday and during the day on Monday with heavy rain expected.
"A complex and slow-moving trough of low pressure affects the North Island until Monday night, bringing rain or showers to many places, with some heavy falls about eastern districts."