NIWA's National Climate Centre says a "near-normal" winter is on the way.
The centre's three-month outlook from May to July forecasts average or above average temperatures across the whole country.
Principal NIWA scientist James Renwick says most of New Zealand is likely to experience near normal rainfalls for the three months.
He says La Nina has weakened to a neutral state in the tropical Pacific and is likely to stay neutral through the outlook period.
However, Dr Renwick says the outlook does not rule out occasional cold spells typical of winter. Nor does it suggest there will be enough rain for drought-affected regions.