The good news for holiday makers is that New Zealand has a ridge spreading over us from the Tasman Sea, bringing mainly fine weather on Christmas Day. However, there is some troublesome low-level moisture underneath this ridge, leading to a few cloudy areas and afternoon showers.
Strong temperature contrasts mark the run-in to Christmas, with warm northwesterlies bringing hot temperatures early in the week ahead of an approaching front. Behind the front, a southerly change could knock as much as 10 degrees off temperatures as it crosses the South Island on Tuesday, although temperature changes will be less as the southerly change passes over the North Island on Tuesday. After this, a developing ridge heralds more settled conditions over the Christmas break and temperatures climb again, although they won't reach the same heights as earlier this week straight away. On Christmas Day, Auckland and Christchurch should reach the low 20s, while Wellington will hit the high teens. By Boxing Day Central Otago, Marlborough and inland Canterbury look likely to bask in the heat again.
On Christmas morning, any lingering cloud should break up with the heat of the day revealing blue skies in most places. Gisborne can expect to start with sunshine, but the cloud will increase all along the east coast in the evening. Inland areas of both islands will see a few afternoon and evening showers, especially the eastern ranges of the North Island. To find out if these showers could affect you, check the forecast for your area on metservice.com.
Boxing Day looks to be a stunner of a day, with clear skies and just a slim chance of a shower for inland parts of the South Island. Looking further ahead, the high should stick around with fine weather persisting for several days into early next week.
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