Summer has left a trail of rain and heat records - and most of New Zealand can expect above-average temperatures and rainfall to extend through autumn.

In its March to May seasonal outlook, Niwa says temperatures around the country are forecast to be above average.

The downside is that rainfall is forecast to be above normal in the North Island and in the north of the South Island. The west and east of the South Island are forecast to receive normal levels of rainfall.

The good news for farmers is that soil moisture levels and river flows are forecast to be above normal in the north and west of the North Island and the north and east of the South Island.

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Niwa predicts temperatures to be higher than usual for New Zealand during autumn. Image / Niwa
Niwa predicts temperatures to be higher than usual for New Zealand during autumn. Image / Niwa

These levels are forecast to be normal in the east of the North Island and the west of the South Island.

As autumn progresses, frosts may occur from time to time in cooler locations.

Niwa predicts rainfall to be higher than usual for New Zealand during autumn. Image / Niwa
Niwa predicts rainfall to be higher than usual for New Zealand during autumn. Image / Niwa

February was the wettest since records began for Nelson and Blenheim, while the rest of the country experienced what's being labelled an "unsettled" month.

Nelson airport recorded 234mm, a whopping 370 per cent of the normal February rainfall.

Rain readers at Blenheim Airport recorded 199mm, or four times the normal amount for the area.

MetService meteorologist Georgina Griffiths said although the amount of rain was unusual, February was often "boom or bust" in terms of wetness.

"The month is often characterised by deluge rainfall — or none at all."

As summer draws to a close, a round-up of February's weather statistics shows that frequent lows and persistent northerly winds resulted in an extremely wet month across the country.

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Main centres like Auckland, Hamilton, Wellington and Christchurch all experienced more than 200 per cent more rainfall than usual over the month.

Niwa says the warm and humid forecast for the North Island is linked to lower than normal atmospheric pressure northwest of the country and warm ocean waters.

Weak La Nina conditions were behind much of February's unsettled weather, but the system was now decaying.

As La Nina wanes over the next three months, New Zealand's regional climate is expected to be driven by the warmer-than-average waters in the Tasman Sea and Southwest Pacific, which will influence surface air temperatures and the likelihood of significant rainfall.

Models indicate a transition towards El Nino over winter and into the September to November period.

Autumn outlook

Northland, Auckland, Waikato, Bay of Plenty

Temperatures are very likely to be above average (70 per cent chance).
Rainfall totals are most likely to be in the above normal range (50 per cent chance).
Soil moisture levels and river flows are most likely to be in the above normal range (50 to 55 per cent chance).

Central North Island, Taranaki, Whanganui, Manawatu, Wellington

Temperatures are very likely to be above average (70 per cent chance).
Rainfall totals, soil moisture levels and river flows are all most likely to be above normal (45 to 50 per cent chance).

Gisborne, Hawke's Bay, Wairarapa

Temperatures are very likely to be above average (70 per cent chance).
Rainfall totals are most likely to above normal (45 per cent chance).
Soil moisture levels and river flows are equally likely to be in the above normal range (40 per cent chance) or near normal range (40 per cent chance).

Tasman, Nelson, Marlborough, Buller

Temperatures are very likely to be above average (70 per cent chance).
Rainfall totals, soil moisture levels and river flows are all most likely to be above normal (45 to 50 per cent chance).

West Coast, Alps and foothills, inland Otago, Southland

Temperatures are very likely to be above average (60 per cent chance).
Rainfall totals, soil moisture levels and river flows are all about equally likely to be near normal (40 per cent chance) or above normal (35 per cent chance).


Coastal Canterbury, east Otago

Temperatures are very likely to be above average (70 per cent chance).
Rainfall totals are about equally likely to be in the above normal range (40 per cent chance) or near normal range (35 per cent chance).
Soil moisture levels and river flows are most likely to be in the above normal range (55 per cent chance).