The past 12 months have been marked by extreme weather with New Zealand recording its fifth warmest year in more than a century.
Niwa today released its annual climate summary for 2017 saying the past year was a "year of extremes".
Annual rainfall was above normal across the country and for some regions including Auckland, Waikato, Bay of Plenty, coastal Canterbury and north coastal Otago, as much as 149 per cent.
• 2017 - Four seasons in each season
It was an especially wet year in Oamaru which had its second wettest year on record - 813mm of rain - and its wettest winter ever. On July 21 a whopping 161mm of rain fell making it the wettest day in the town since records began in 1950.
Highs and lows
At the same time the country enjoyed higher than usual temperatures, becoming the 5th warmest year since records began in 1909.
January was the only month where temperatures fell below average with six months recording above average temperatures.
April, August, September, October and November were all between .7C to 1.3C above average with December 2.4C above average.
While sunshine was near normal across the country Nelson was the sunniest region with 2633 hours of sun.
Niwa described 2017 was a year of two halves. The year started off on a west and stormy note across the South Island in January before reaching record or near-record rainfall and flooding across the North Island during the "Tasman Tempest", ex-Tropical Cyclone Debbie and ex-Tropical Cyclone Cook that swept through in March and April.
Later in the year parts of western and lower North Island were in a meteorological drought as very dry weather in November led to major decreases in soil moisture.
Niwa said Christchurch observed just a single mm of rain during November, the driest November on record. The city had a 47-day dry spell that was broken mid-December.
Sea surface temperatures also fluctuated starting off the year at normal levels but up to 4C above average as a "marine heatwave" hit coastal waters in November in December.