Summer is set to be a scorcher

There will be more Aucklanders on the beaches this summer as the weather will be in the late 20s. Photo / Doug Sherring

Get ready to crank up the barbecue, grab the sunscreen and hit the beaches, with summer shaping up to be hotter than last year.

A warmer and drier end of spring and start of summer was expected for most of the country due to the La Nina weather system, according to Niwa's seasonal climate outlook.

From now until December, temperatures were likely to be average or above average in the North Island and north of the South Island.

By December, Aucklanders could expect days in the mid 20s and above - one to two degrees warmer than usual.

Wellington and Christchurch were likely to have days in the low 20s, and in Dunedin the temperatures could be in the high teens.

"The chances are that it will be at least that warm and possibly warmer," said Niwa principal climate scientist Dr James Renwick.

The La Nina weather system was developing in the tropical Pacific and expected to continue over the summer season, according to Niwa.

It would bring big pressure systems and northerly winds, creating warmer air temperatures than usual, said Renwick.

With a hot summer on the cards, Surf Life Saving New Zealand expected volunteers to be working more hours as people flocked to the beaches, said spokesman Brett Sullivan.

Last year lifeguards worked more than 200,000 volunteer hours on beaches - more than ever before, said Sullivan.

But the warm weather wasn't good news for farmers.

The weather system meant "chances are it will get a little bit drier as well", said Renwick.