Heating up - spring arrives with a flourish

The temperature in some eastern parts of the country could reach 25 degrees Celsius within a few days as spring arrives at a gallop.

Niwa is predicting the arrival of spring tomorrow and said subtropical winds flowing south from near New Caledonia would make the end of the week feel more like November or December at times.

The warm spell could last from tomorrow through to next Tuesday, and records could tumble, Niwa said.

New Zealand remained on course for the warmest year on record, Niwa forecaster Ben Noll said.

Despite August being ‘‘a bit of a chilly month’’, it hadn’t stopped the January to August period being the warmest first eight months on record since Niwa’s seven-station series started in 1909.

‘‘We will probably find the temperature for the month of August will be below average.

‘‘But it seems as if the weather is picking back up as we move into spring,’’ Noll said.

August would have needed to be ‘‘much cooler’’ than it was to knock the first eight months out of first place, and it would take ‘‘quite a bit of a bump’’ for 2016 as a whole not to be the warmest year on record.

In the shorter term, a couple of rounds of record-breaking temperatures were possible.

‘‘We are forecasting unseasonable warmth on Thursday and Friday across the east of both islands, where temperatures may rise to between 5 and 10C above the average maximum daily temperature,’’ Noll said.

Some places – possibly Canterbury or Hawke’s Bay – might approach 25C as a classic foehn wind developed.

‘‘The atypical warmth is expected to expand across the North Island by the weekend and may get more impressive from Sunday for couple of days when records could tumble.

‘‘There is the potential for another round of record-breaking temperatures just after September 10.’’

Some temperature records were broken during winter, with Napier and Gisborne having record warm winter temperatures on June 10 – 25.1C and 23.2C, respectively.

Timaru was headed for its sunniest winter on record since 1930, with 510 hours through to August 28.

Unusually warm seas around the country continued to contribute to high temperatures, while the El Nino weather pattern had played a big role from 2015 into 2016, Noll said.

Climate change was also part of the overall recipe for warming, with 2016 above the trend ‘‘no doubt about it’’.