An active front over the North Island is forecast to weaken from late Tuesday.
Metservice said there was a 40 per cent likelihood of rainfall accumulations reaching warning criteria over Taupo, Rotorua and the Bay of Plenty.
There was also moderate confidence rainfall would reach warning criteria over the ranges of Hawkes Bay and Gisborne, Waikato from Morrinsville eastwards, Coromandel Peninsula, Auckland including Great Barrier Island during Tuesday.
A ridge is forecast to move north over the North Island on Thursday after hitting the South Island on Wednesday.
Metservice issued a severe weather warning this morning, for periods of heavy rain and possible thunderstorms.