Hot weather, with highs into the 30s, will great some people across both islands over Monday and Tuesday this week – but another cold southerly is coming for the South Island with highs set to tumble on Wednesday, especially in the deep south. However northern New Zealand is unlikely to be significantly affected by this change – with mostly dry and sunny weather remaining. The good news is that a high will move in on Waitangi Day – but a few areas will have morning showers and brisk, cool, northerlies. Chance of a shower at Waitangi itself, otherwise dry with passing clouds and an easterly wind.