Normal to dry weather is likely for the North Island and in Nelson-Marlborough.
Rainfall in these areas is forecast to be lower than usual.
A combination of La Nina and easterly winds last year brought a cloudy, wet summer for the North Island and Nelson-Marlborough, said Mrs Griffiths.
"This year we're forecasting more southwesterlies, so that's the reverse of last year. We're expecting dry weather in the northeast of the North Island.
"Everywhere else we're expecting normal summer rainfall - it depends on where you live what that means," she said.
Western areas from Taranaki to Wellington and the West Coast of the South Island and Southland can expect temperatures to be average or slightly below average overall.
Everywhere else temperatures will be average.
"For the bulk of the population I would say it's a much better forecast than the one we had last year."
But the weather won't be good news for everyone.
An unusually dry November for many regions, including much of the North Island and Nelson-Marlborough, dried out the soil and the average rainfall forecast would bring only limited relief to the areas, said Mrs Griffiths.
The east coast of the North Island, north of Taupo, Hawkes Bay, Wairarapa and Nelson would have drier than normal soils for summer.
"If you're a holidaymaker, excellent, and if you're a farmer perhaps not so good in those regions.
"They'll get some rain over summer but we're forecasting below normal rain for them."
And if you're looking for settled, warm weather over the summer, the traditional hotspots are your best bet, said Mrs Griffiths.
"If you want settled, hot perhaps if you think about what's typical for the summer, it's always warmest in the northern North Island, so Coromandel or Gisborne, Hawkes Bay and parts of Canterbury are quite warm for summer.
"The dry forecast is really in the northern east, so my bet would be on Coromandel, Bay or Plenty, or Gisborne, Hawkes Bay.