Don't bank on firing up the barbie on Christmas Day.
The weather will be a "mixed bag'' with rain possible around the country, according to MetService.
Spokesman Daniel Corbett said fine weather would continue this weeks although troughs would bring rainfall as they moved up the country.
"These troughs should bring some wet spells in places this week, but between these the drier days will be decent for outdoor plans.''
The first trough would move up the country today and tomorrow, bringing showers and rain followed by slightly cooler air.
The afternoon heat would also generate thunderstorms, which could be severe at inland North Island locations, Mr Corbett said.
A second trough would spread another band of rain or showers up the country on Wednesday and a third may appear over the weekend.
"The exact details of the weather for early next week and the run-up to Christmas still need to iron themselves out, but at this point it seems the weather might continue to be a mixed bag,'' Mr Corbett said.
"It's not going to be an ugly sabre-toothed tiger, but there might be some spots of rain around the country.''
Current MetService forecast for Christmas Day:
* Auckland: Showers, westerlies. High of 21, overnight low of 16.
* Hastings: Showers, light winds. High of 22, overnight low of 15.
* Hamilton: Showers, little wind. High of 21, overnight low of 13.
* Wellington: One or two showers, northwesterlies. High of 17, overnight low of 15.
* Christchurch: Partly cloudy at first then rain with not much wind. High of 19, overnight low of 12.