Paihia sää — huhtikuu

The date regulars keep repeating for this town is the 23rd of December: from there the New Zealand holiday period starts and accommodation becomes very hard to find, with the bay cruises filling alongside it. Early December is the quieter half of the same weather. And the weather here is the country's kind end - 21.9C reading as 23C over 16C nights, 50.5mm across 9.2 days, and 11.5 hours of sun inside 14.5 of daylight, which is a gentler December than the capital gets at the other end of the country. The sea is 19.2C, swimmable rather than warm, and a 21.8 kph breeze off the bay keeps the afternoons comfortable. The record: humidity 78 percent and AQI 24.

January and February are the warmest months in the Bay of Islands - shorts weather, with a light jacket for an evening that can still turn humid rather than cool - and regulars give February the edge on weather and on fishing, with March the quieter alternative. What January has over February is price and space: February is the peak holiday stretch, and early February around Waitangi Day on the 6th is when tours and rooms get both crowded and dear. Our row is honest about the trade: 23.3C over 17.4C, but 83.6mm across 9.8 precipitation days, so a New Zealand January is not a dry summer. The record: humidity 77 percent, 11.7 hours of sun, a 22.2 kph wind, a 21.4C sea and AQI 27.

February is the Bay of Islands' most settled month, with March its near-equal and the fishing better in February - which is also why it is the most expensive. Waitangi weekend at the start of the month is the pinch point, when accommodation goes to a premium and wants booking well ahead. March is the alternative regulars offer: very nearly the same weather with smaller crowds. The boats are the point here, out to the Hole in the Rock, with sundowner cruises running December to March and the day trips October to May. The record: 23.3C days that feel like 24C, 18.1C nights, 9.3 precipitation days carrying 80.1mm, 10.9 hours of sun and a 22C sea.

Bay of Islands forum threads describe September temperatures hovering around 18-19C, with the recommended packing list being layers - jeans or long trousers, a cotton or long-sleeved top, and a warm jacket for outdoors - reflecting a subtropical-but-not-warm early-spring climate. Posters were direct that it's still too cold for a beach swim this time of year, though nothing too heavy is needed given the region's mild northern New Zealand setting. Spring here was described as genuinely windy and changeable more broadly, with reasonable rain on and off through the month rather than settled, predictable conditions.