Christmas Day weather forecast: what to expect for the holiday

Christmas day celebrations may need to be inside for the parts of the country, as a forecaster says it may not be a nice, settled story that many of us are hoping for.

With only eight sleeps until Christmas, we are in the meteorological window of predictability, and while the forecast for Christmas day could change, the east coast is shaping up to the be the place to be.

The week before Christmas has been rainy and windy, as cool temperatures in the upper atmosphere over central New Zealand causes unstable conditions.

There is a risk of thunderstorms for parts of the day from South Auckland down to mid-Canterbury, MetService said.

MetService meteorologist John Law told RNZ the unsettled weather will continue throughout out Wednesday.

"It does get better for places like Auckland and down the western side of New Zealand as we head in towards tomorrow, but the week is still looking very unsettled."

But the question on everyone's mind is what the weather forecast will be for Christmas day.

"The million-dollar question is that lead up towards Christmas, how are things panning out?" Law said.

"... I don't think we are going to quite find it's a nice, settled story that many of us are hoping for."

He said low pressure systems from the west turn the country into a westerly set up next week.

Westerly weather brings more cloud and longer spells of rain for the west of the South Island. In the North Island, the further west you are, the more likely there will be cloud and perhaps some showers, Law said.

"As we are heading towards Christmas day, the east coast might be the best place to be," he said.

MetService is forecasting temperatures in the 20s for much of the country on Christmas day.

MetService's Christmas day forecast:

• Auckland: High of 25C, low of 17C
• Tauranga: High of 25C, low of 16C
• Hamilton: High of 24C, low of 13C
• Wellington: High of 20C, low of 14C
• Christchurch: High of 23C, low of 11C
• Dunedin: High of 19C, low of 11C
• Invercargill: High of 17C, low of 9C

However, with any forecast that goes out beyond a week, there is a likelihood it could change, Law noted.

"So, the forecast is by no means set in stone. It's always worth making sure you keep up to date with the forecast for those subtleties and nuances as the forecast gets closer and closer and change your plans accordingly."

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