Thornton Bay, New Zealand offers 1 beach perfect for sunbathing, surfing, swimming, and more. Thornton Bay is known for its proximity to the Coromandel Peninsula and the scenic beauty of the Firth of Thames. The best time to travel to Thornton Bay, New Zealand, is during the summer months of December to February, when the average air temperature is around 22°C (72°F) and the water temperature is approximately 20°C (68°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!