Heavy rain is falling across the top of the North Island today, soaking an already flood-ravaged Northland, while motorists travelling across the Auckland Harbour Bridge face restrictions due to high winds.

More than 200 properties are also without power in Northland after falling trees downed powerlines overnight.

MetService has issued heavy rain warnings for Northland until 2pm, Auckland north of the harbour bridge and Aotea Great Barrier Island until 6pm, and the Coromandel Peninsula until 2am tomorrow.

Auckland Emergency Management warned the city’s residents that after a night of wet weather “unfortunately there’s more to come”, asking them to take extreme care and plan ahead, especially on the roads.

“Drive to the conditions and never drive through floodwater. Do not walk or play in floodwater, it can be contaminated, and contain hidden hazards and debris.

“If your life or property is at risk, phone 111.”

The New Zealand Transport Agency (NZTA) has warned motorists to drive to the conditions across the harbour bridge with wind gusts of 75-85km/h forecast between 7am and 8pm today.

An electronic message board on the motorway this morning was warning motorists to take extra care, with speeds on the bridge limited to 70km amid strong wind gusts.

“The bridge will remain in 4x4 configuration throughout the day,” a spokesperson said.

“Motorists are advised pay attention to electronic message boards on the motorway, which will advise if any lane closures and reduced speed limits are required.

“If there is a potential for sudden and high wind gusts on the bridge, lowering the speed limit gives motorists time to react and take more care.”

In Northland - already soggy from the weekend’s destructive deluge - the rain had been moving quickly overnight, according to MetService. That meant rainfall rates had been manageable, the forecaster’s lead meteorologist Alain Baillie said around 5.30am.

“We’ve been lucky, it’s been moving on pretty rapidly and it’s eased off up there now,” Baillie told the Herald. However there would be periods of heavier rain until early afternoon.

Rainfall rates were “pretty moderate compared to the weekend when we had well over 100mm in a very short time”, Baillie said.

“As far as warning areas goes it’s been pretty manageable.”

There are also 269 properties in Northland without power after trees reportedly fell on high-voltage power lines, cutting customers off from the grid from 1am.

Northpower, an electricity company that supplies power to 63,000 Whangārei and Kaipara customers, said affected customers will be out of power for at least an hour as a team heads to the site to restore the network.

“We will not have an estimated time of restoration until the work required has been assessed,” Northpower said in a notice on its website.

“Please treat all lines and equipment as live at all times.”

Eastern Northland had been the hotspot with Whangārei receiving 40mm of rain in the 12 hours to 5am. Kerikeri had received 35mm, Waitangi 25mm and Warkworth 24mm. The highest rainfall total was 64mm in Glenbervie Forest, just north of Whangarei.

Thanks to the rain moving quickly, nowhere had received more than 10mm/hour in that period, Baillie said.

By comparison, the Herald has reported some areas saw peak rates of 80mm/hour during the weekend’s deluge, with Punaruku receiving a whole summer’s worth of rain - 285.5mm - in 24 hours.

MetService forecaster Alannah Burrows yesterday said the “wedge of warm moist air”, which arrived from the tropics yesterday, would continue to bring wet weather across the very top of the North Island.

“We are going to see those showers turning into more persistent rain with heavier falls and a chance of thunderstorms with localised downpours for Northland,” she said on Monday.

Burrows said periods of rain would be heavy throughout the day.

‘Impactful’ weather event on Wednesday

The bad weather won’t be over with today’s heavy rain. Tomorrow, a low-pressure system originating from the tropics will move towards New Zealand.

“As it does, we are going to see more persistent rain developing over that region, with some heavy rain likely,” Burrows said.

“We are expecting a moderate risk of some warnings being issued for those regions for heavy rain.

“There is a moderate risk with some severe gales associated with that.”

Burrows said there was a risk this “impactful event” would cause flooding across the affected regions.

Civil Defence Northland has encouraged people in the region to remain prepared for unsettled conditions as rainfall totals might “approach or exceed warning criteria in some areas”.

Whangārei Mayor Ken Couper said eyes are now turning to the rainy weather later this week, “which may produce further landslips and disruption”, while roading crews try to clear slips and open roads as much as they can.

Speaking to Newstalk ZB, Couper said those in the worst-hit areas believe the recent flooding is worse than Cyclone Gabrielle, but the council is doing all it can to help those affected.

“We’ve got saturated ground already. If we get more rain, it’s continuing with light rain up here. If we get more rain and it’s heavy, we want to be ready for that.”