The Bay of Plenty is one of NZ's sunniest regions: Whakatane records a brilliant 2350 average hours of sunshine per year! In summer (December to February) maximums hover between 20°C and 27°C. Everyone else is here, too, but the holiday vibe is heady.
Visit Rotorua any time: the geothermal activity never sleeps, and there are enough beds in any season.
The mercury can slide below 5°C overnight here in winter, although it’s usually warmer on the coast (and you'll have the beach all to yourself).