Temperatures dramatically above average are unlikely to continue throughout spring.
Sunny weather across much of the country over the weekend marked the end of one of the warmest winters on record.
But a return to more normal temperatures is likely over the September to November period, according to Niwa National Climate Centre's seasonal climate outlook.
Spring temperatures are likely to be near or above average temperatures across New Zealand, and residents in the upper North Island will still need the umbrella, with rainfall totals in the region likely to be in the near normal or above normal range.
WeatherWatch head analyst Philip Duncan said people would not notice the same unseasonable warmth over spring. "The next month or so is probably going to be fairly average to slightly above average.
"It's not going to be as dramatically warmer than it was in the middle of winter when we really noticed how much warmer it was [than] average."
Mr Duncan said a cold change would arrive around Wednesday, when rain was predicted for Auckland. "It is going to feel like winter again, just briefly. That's normal for spring, which is all about reminders of winter, but also that summer is on the way."
High pressure systems were predicted for later in the month, meaning drier days would balance wet ones. Mr Duncan said westerly winds would also become common later this month.
Recent spells of sunshine had turned people's minds to summer, he said, but long-range predictions of what to expect were perilous.
But he said the current "chaotic" weather system, marked by the absence of both La Nina and El Nino, tended to bring extreme weather events, but also warmer weather.
"It throws everything at us - but it does tend to bring warmer weather, and probably drier. My feeling is that this summer has a higher risk of being dry than a normal summer would."