MetService has issued a severe thunderstorm watch for the Bay of Plenty region that will last five hours.
The watch will be in effect from 3am to 8am on Wednesday.
It comes after residents living near flood-prone waterways in Rotorua are urged to stay on high alert or even relocate tonight as bands of heavy rain roll over the Bay of Plenty region.
An orange heavy rain warning remains in place for the entire region and Coromandel through to Wednesday morning, with up to 180mm of rain expected.
Downpours of 25 to 40 mm/h are expected, especially east of Kawerau - potentially bringing flash flooding, slips and hazardous driving conditions.
The NZ Transport Agency has warned drivers the worst of the weather may coincide with high tide around 10.30pm, increasing the risk of flooding in low-lying areas and coastal zones.
Motorists were urged to slow down, increase following distances and drive to the conditions. Watch for surface flooding, slips, and debris and avoid driving through floodwaters.
Monster swells have begun smashing the Bay of Plenty coastline, where waves have reached 6.4m at Pukehina.
They have also reached 5.9m at Tauranga.
MetService said there was a moderate chance the orange warning could be upgraded to red, and warned streams and rivers could rise rapidly.
“Clear your drains and gutters to prepare for heavy rain. Avoid low-lying areas and drive cautiously.”
A strong wind watch is also in place for Coromandel Peninsula, eastern Waikato and Bay of Plenty, with northeast winds approaching severe gale force in exposed places.
Rotorua Lakes Council said residents living by waterways that are prone to rising during heavy rain were urged to stay on high alert.
“Particularly those along the Ngongotahā Stream who should consider staying elsewhere tonight, as a precaution, until the weather event passes,” the council said.
“If you don’t have somewhere you can stay, contact Rotorua Lakes Council on 07-348 4199.
“Rotorua Lakes Council Civil Defence staff are closely monitoring the developing situation, in collaboration with Bay of Plenty Civil Defence staff, and taking steps to ensure they can respond if/as needed.”
Tauranga City Council emergency management duty controller Sam Fellows said the on-duty team continued to monitor the forecast closely.
“Council service teams have been proactively checking and clearing stormwater grates and outlets across the city.
“Please stay safe if you’re out and about. Be aware of potential surface flooding, slips, and strong northerly winds.”
🌊 Big waves rolling in 🌊
— MetService (@MetService) July 28, 2025
Strong northeasterly winds are driving up swells along eastern coastlines of the upper North Island 💨
Significant wave height: the average peak-to-trough height of the highest one-third of the waves. This is what you’d generally ‘eyeball’ the wave… pic.twitter.com/COAnIU6lB9
Western Bay of Plenty Council Civil Defence local controller Kerrie Little encouraged people to secure trampolines and outdoor furniture, clear leaves and debris from external drains to help prevent surface flooding, charge up mobile phones in case of power outages and check on neighbours.
“If your property has been prone to flooding in the past, move your furniture and valuables as high above the floor as possible, use watertight containers to store important items, and lift curtains, rugs and bedding off the floor.
“Consider using sandbags to keep water away from your home – these can be purchased from local hardware stores – and have a grab bag handy if you feel you may need to evacuate your property.”
“Most importantly, stay informed,” Little said.
“We are actively monitoring the situation and taking a precautionary approach across our operations.
“Pre-rain checks have been completed, our transportation team has inspected key roading sites, and we have essential contractors, such as arborists, on standby.”
Little said anything dangerous like a fallen tree or slip should be reported to the council at 0800 926 732 or the Antenno app.
Bay of Plenty Regional Council said in a statement it had activated its flood room at 9.30am and was liaising with local councils regarding the impact of the rain across the region’s major schemes: Waioweka-Ōtara Rivers Scheme, Whakatāne-Tauranga Rivers Scheme, Rangitāiki-Tarawera Rivers Scheme, Kaituna Catchment Control Scheme and the Rangitāiki Drainage Scheme.
Atmospheric River (AR): a long, narrow region in the atmosphere that transports vast amounts of water vapour, often from the tropics to mid-latitudes.
— NIWA Weather (@NiwaWeather) July 28, 2025
This AR is the fuel for today's heavy rain & impacts associated with heavy rain (e.g., flooding & slips). pic.twitter.com/0vztOtmwvq
The council said as of 11.30am, there were no warnings in place. However, this was likely to change overnight.
“The flood room team do communicate directly with landowners or the occupiers of properties on low-lying rural land next to major rivers within or adjacent to the river floodplain, should rivers expect to reach first and second warning level,” the council said.
“The warnings are pre-recorded voice messages sent via an automated system to a person’s landline and/or mobile phone. These notifications ensure these landowners have time to prepare, for example, moving stock to higher land.“
A first warning level means the river level has reached its normal channel capacity. A second warning level means the river has overtopped the channel banks and has flooded the area next to the river.
This is still well within the flood defences around the river, such as a stopbank or floodway.
Significant heavy rain and strong north to northeast winds expected during Tuesday and into Wednesday morning
— MetService (@MetService) July 28, 2025
A front moving east across the country is expected to bring heavy rain and strong north to northeast winds to several places. People are advised to keep up to date with… pic.twitter.com/AcIdb44pZW
Agriculture Minister Todd McClay said he urged farmers, foresters and growers to prepare for potential challenges the adverse weather may bring.
“MPI staff are ready and available to assist, with additional staff deployed in the top of the South and regional staff closely monitoring the Bay of Plenty. We have 15 MPI staff on the ground in the Nelson/Tasman area and people available across the Bay,” he said.
Farmers were advised to move stock to higher ground ahead of the storm.
“We understand the pressure and uncertainty rural communities are facing right now, and we remain focused on ensuring they have the resources to manage this event and any challenges ahead.”
The heavy rain has also prompted the Department of Conservation (DoC) to close tracks to Coromandel’s Mautohe Cathedral Cove and urge visitors not to go to the famous beach.
DoC Coromandel senior ranger Matt Flynn said it was prudent to close the tracks, given the weather system’s expected impact.
“DoC’s priority for this site continues to be the safety of visitors and managing visitor risk. Poor weather exacerbates the landslide and rockfall risks at Mautohe Cathedral Cove.
“We strongly discourage people from visiting the cove while this weather system moves – the conditions make it unsafe.
“We do not want people getting hurt.”
Flynn said the Mautohe Cathedral Cove closure came into effect from 6am today and would be in place until further notice.
Sea swells are expected to increase with the weather system and anyone planning to visit Mautohe Cathedral Cove by boat should check sea conditions first and consider the risks.