Above average temperatures are expected in the Bay of Plenty with the National Institute of Water and Atmospheric Science predicting a warm summer ahead.

NIWA's seasonal climate outlook for the next three months shows a warm quarter with near or above average temperatures.

A warm summer in Tauranga is expected.

'However, frosts may occur in some areas from time to time. Sea surface temperatures are expected to remain above average overall around New Zealand.”

Temperatures in the October – December period as a whole are most likely to be above average in the east of the North Island.

'In all other regions, average or above average temperatures have near equal likelihood of occurring. The chance of below normal temperatures across all regions is 10-20 per cent.”

NIWA says the equatorial Pacific Ocean continues in a neutral state, neither El Nino nor La Nina, with recent cooler-than-normal sea-surface conditions, La Nina-like, in the eastern tropical Pacific having weakened.

International guidance indicates that ENSO-neutral conditions are the most likely outcome for the next three months.

NIWA expects rainfalls in the next three months to be around the normal 40 per cent chance, or above normal in the north of the north of the North Island, and less likely - 20 per cent chance - to be below normal.

For all remaining regions of New Zealand, near normal rainfall totals are most likely, meaning a 45-50 per cent chance. Soil moisture levels are 40 per cent likely to be normal or above normal in the north of the North Island, and most likely to be near normal for all other regions. River flows are equally likely (40 per cent chance) to be normal or above normal in the north of the North Island, and most likely to be near normal for all remaining regions (45 per cent chance).