A severe weather watch is being issued for the Bay of Plenty as a humid northeast flow is expected to remain over northern New Zealand today and tomorrow.

The MetService is warning rain may become heavy in the Bay of Plenty overnight and potentially reach warning criteria tomorrow, with thunderstorms possible.

Rain accumulations could reach short duration warning criteria with more than 50mm expected to fall in six hours.

'Note, further localised downpours and thunderstorms are possible tomorrow.

'In addition, rain is expected to become heavy about the Coromandel Peninsula this afternoon and this watch is for the possibility of warning amounts of heavy rain there, with thunderstorms possible tomorrow. Rain should ease tomorrow afternoon.”

Bursts of localised heavy rain are also expected in Northland and Auckland until this evening.