King tides have also been forecast, which coupled with strong north-easterly winds could lead to coastal inundation in places.
MetService meteorologist April Clark said New Zealand would say goodbye to the calm weather experienced over the past few days as the low moves to the northeast, spreading rain over the country this week.
A Western Bay of Plenty Council spokeswoman said teams were out all day yesterday checking systems in preparedness for heavy downpours.
She said residents should check drains and culverts and if they spot any blockages to report it to the council.
The public is advised to call emergency services for any house flooding and head to the council's website for further information.
A spokeswoman from the Tauranga City Council said people should ensure their roof gutters are clear and in good order and they have a good supply of sandbags if their property is prone to flooding.
She said the council's contractors had crews ready to assist when necessary.
A spokeswoman from the Rotorua Lakes Council said they were monitoring the weather closely and had been preparing for downpours.
These preparations included inspection of critical stormwater systems, lowering of wastewater storage pond levels and monitoring of reports of surface flooding, slips and treefalls.
She said they will also monitor rain gauges and water levels in Rotorua's waterways and will alert council to rising water levels that may require the community to be alerted or any emergency action to be taken.
TODAY'S FORECAST:
Tauranga - Rain, possibly heavy and thundery, easing in the evening. Strong northeasterlies easing in the afternoon. High of 18C, low of 13C.
Rotorua - Rain, possibly heavy and thundery, easing evening. Northeasterlies. High of 16C, low of 13C.
Whakatane - Rain, possibly heavy and thundery, easing in the evening. Strong northeasterlies easing in the afternoon. High of 17C, low of 13C.
