The latest seasonal climate outlook from the National Institute of Water and Atmospheric Research (NIWA) suggests temperatures are likely to be above average across the entire country over coming months.
The outlooks indicate the likelihood of climate conditions - like air temperatures, rainfall, soil moisture and river flows - being at, below or above average for the season. They're developed by NIWA scientists observing atmospheric and ocean conditions as well as the results of both global and local climate models.
The latest outlook released on Friday covers August to October and suggests temperatures "are most likely to be above average in all regions of the country".
"More northwesterly air flows will likely cause spells of unseasonably warm temperatures in the north and east of both islands in particular," the report summary says.
Higher than normal air pressure, especially in the north and east, is expected "to bring spells of drier than normal conditions to many regions through the three month period along with more northwesterly quarter winds (westerly to northerly)".
"Rainfall is about equally likely to be near normal or above normal in the west of the South Island, most likely to be near normal in the west of the North Island, and about equally likely to be near normal or below normal in all remaining regions."
NIWA also says that it is moving into "La Niña Watch, acknowledging ocean and atmospheric conditions in the Pacific Ocean that are trending toward La Niña".
"The climate system is showing similarities to this time last year, which featured La Niña development during spring – these similarities are reflected in the rainfall and temperature outlook. This information may be useful for planning purposes over the coming season."
Sea surface temperatures ranged from 0.7C to 1C above average in July, NIWA says, and it's predicted they will remain warmer than average.
"Soil moisture levels are about equally likely to be near normal or below normal in the east of the North Island and most likely to be near normal in all other regions.
"River flows are about equally likely to be near normal or below normal in the north and east of the North Island and north of the South Island and most likely to be near normal in all other regions."
