Meanwhile in the South Island a cold front will start to move through, bringing rain up the west coast towards the North Island.
A heavy rain watch is in place for Fiordland, Westland and Buller, as well as the Tararua Range.
It's not getting any better on Tuesday either - periods of rain and showers are expected for much of the country, though fine weather may show its face in parts of the South Island, aside from Southland and the West Coast.
Between Wednesday and Friday strong, cold winds will be sweeping through, and showers will be developing over many places.
But it's not all bad news. Vuksa said Friday is currently forecast as being fine for most of New Zealand, just in time for the weekend.
Monday's forecast
Auckland: Cloudy with westerly winds. High 17C, low 10C.
Tauranga: Partly cloud with westerly winds. High 17C, low 8C.
Wellington: Cloudy with scattered rain in the evening and strong northerly winds. High 14C, low 10C.
Christchurch: Increasing high cloud with northerly winds dying out overnight. High 19C, low 4C.
Dunedin: High cloud with light rain from midday, fine in the evening. High 15C, low 9C.