The Metservice advise that a low which is expected to affect the upper North Island during Monday, is forecast to move slowly east towards Bay of Plenty on Tuesday, then move away on Wednesday.

This low brings rain or showers to many parts of the North Island and upper South Island, with a strong southeasterly flow over central New Zealand.

"There is a moderate confidence that rainfall accumulations could approach warning amounts about the Wairarapa and central Hawkes Bay on Tuesday," says a MetService spokesperson.

"A ridge of high pressure spreads over the country on Thursday, then moves slowly away on Friday, as a front approaches the South Island from the south Tasman Sea."