Last year was New Zealand's second warmest on record, says climate scientist Dr Jim Salinger.
After compiling data from 22 land stations and three islands, Dr Salinger said that he found the annual mean temperature was nearly one degree higher than average.
The Auckland-based weather expert also found that mean temperatures were well above average in the months of March, July, August and November and record mean temperatures were noted in Masterton, Omarama, Timaru, Invercargill and the Chatham Islands.
Further, Dr Salinger found that temperatures during the winter months last year were nearly 1.3 degrees above the long-term average, which made it the warmest winter since records were first kept 150 years ago.
The New Zealand region had only two cooler than average years - 2004 and 2009 - in the past decade, he said.
The 10-year mean temperature for 2004-2013 was 0.26 degrees above average, the highest on record.
Dr Salinger's findings follow the release of a report which claims 2013 was Australia's warmest year on record.
Last week, a report released by the Australian Bureau of Meteorology said that area-averaged mean temperature for the nation last year was 1.2 degrees Celsius above average.
While preliminary data for the January-November period from the World Meteorological Organisation (WMO) indicates that the estimated global mean temperature for 2013 is 0.49 degrees Celsius above the long-term (1961-1990) average of 14 degrees Celsius.
Dr Salinger said 2013 ranks as the sixth-warmest year since global records commenced in 1880.
He said no year since 1985 has recorded a below-average global mean temperature and nine of the ten warmest years have occurred in the past 12 years (2002-2013).
In New Zealand, he said the warmer weather could be put down to a neutral El Nino-Southern Oscillation (ENSO).
Dr Salinger also said that the Interdecadal Pacific Oscillation (IPO) was negative, which favours more easterlies and north easterlies at times with above average temperatures.
"At the same time sea surface temperatures were above average by around one degree Celcius, especially surrounding the South Island and to the east," he said.
Further, Dr Salinger said ENSO neutral conditions are expected to persist at least until winter 2014, and negative IPO conditions are very likely to persist for the remainder of 2014.
"These conditions are presaged to bring above average temperatures of 0.2 to 0.6 degrees Celsius above average for the New Zealand region," he said.
Dr Salinger claimed New Zealand regional temperatures have warmed by 0.5 degrees Celsius since 1950 and over one degree overall.
"This is similar to what has occurred globally, and the general trend is expected to continue," he said.
Meanwhile, figures from the UK Met Office predict that the global average temperature is expected to remain between 0.28 degrees Celsius and 0.59 degrees Celsius above the long-term (1971-2000) average during the period 2013-2017.