That means long, dry periods, particularly in the North Island, and no sustained run of rain.
"[The La Nina] is fairly weak at this stage. It was very strong last summer and then it fizzed out in the winter, but it's come back again," Dr Renwick said.
"In the north - Auckland and further north - the summer rain tends to come in pretty sharp bursts. It'll be the normal amount of rainfall [but] you might get that in two or three days in a month - a big downpour and then a long period of fine."
Last summer was a record-breaker with heatwaves creating the hottest February on record for Auckland and Nelson.
The average afternoon temperature in Auckland was 25.8C.
Barely a drop of rain fell in the central North Island last month. Taupo and Ohakune had only 2mm of rainfall. In a usual February, Taupo would get 90mm of rain.
Temperatures are not expected to hit record-breaking levels this summer, however hot spots include areas on the East Coast of the North Island such as Gisborne and Hawkes Bay, as well as the Bay of Islands, Bay of Plenty and Mt Maunganui.
The outlook also shows only a slim chance of any tropical cyclones headed towards New Zealand, according to Dr Renwick.
MetService is set to issue its outlook for next month's weather next week.
Weather ambassador Bob McDavitt said yesterday that, generally speaking, the summer would bring slightly drier conditions than usual in the northern end of the country.
The South Island, where it had been dry in the past month, should expect a normal rainfall in the next few months.
Dr Renwick said there was a possibility the La Nina weather pattern could make for varying results, not in New Zealand but in wider parts of the Pacific including Australia and Tuvalu, where there has been a drought.
"I think they are expecting a bit more than normal rainfall in parts of Queensland, but I would hope that it's not going to be anywhere near as manic as last year.
"It's looking like the region from the northern [Cook Islands], through Tuvalu and maybe up to the northwest will probably stay on the dry side for at least two to three months ... not ideal, but that's the way things are looking."
LAZY, HAZY DAYS
* This summer is expected to be long, hot and dry.
* The current La Nina pattern will be in most parts of the country.
* Big downpours of rain will be followed by long periods of fine weather.