A heavy rain watch has been issued for Rotorua and Bay of Plenty as the active front causing flooding and slips in the South Island moves north.
MetService issued a yellow watch and said Bay of Plenty, from Rotorua eastwards, could expect periods of rain with heavy falls between 8pmTuesday and 2pm Wednesday.
The active front over Westland is expected to move across the North Island tomorrow and connect with a low developing north of Northland as well as with a larger and deeper low developing just east of central New Zealand.
This continued to be a significant severe weather event, MetService said.
Meteorologist Lewis Ferris said Bay of Plenty could expect cloudy weather with passing showers before more persistent rain set in overnight.
"It looks like it will be heavy for a time in the morning with strong northerly winds. Winds turn westerly in the second part of the day and the wet weather looks to ease back."
Showers on Thursday clear away to fine weather on Friday and into the weekend.