Saturated land won't have much of a chance to dry out with more heavy rain on its way to drench the country, WeatherWatch says.
Rain is due to arrive on Tuesday and stay until Friday, and another low is forecast to follow.
Forecatser Philip Duncan said this month was shaping up to be an extremely wet month for some areas.
Last month the Bay of Plenty received over half a metre of rain - and this month has started off much wetter.
However next week's low will bring with it warm winds, which means the chance of frosts would be slim.
"While it's mostly good news for farmers it's not great news for North Island ski fields which could do with a decent southerly and a big snow dump," Mr Duncan said.
Warm winds with sub-tropical connections will spread down across parts of the nation, he said.
"Spring hasn't arrived, even though we have spring weather for some at the moment, but...I think we've past the coldest point of the year despite being smack bang in what is historically the coldest period of the year for New Zealand."
Forecaster Howard Joseph said the rain associated with next week's low will likely be confined to the North Island and upper South Island on Tuesday.
But he said it would not be wet for everyone.
"During this low's visit, it looks like the lower half of the South Island should remain dry.
"By Thursday morning, the centre of the low should move off our eastern shores and head out to sea. Some bands of light showers may linger in its wake. But most areas will see the weather start to clear. Then it's time for the next low."