Weather: What you need to know about Cyclone Gabrielle right now

A national state of emergency has been declared for the third time in New Zealand's history as the country deals with widespread damage as a result of Cyclone Gabrielle. 

Gisborne

The Gisborne/Tairāwhiti region is still without power or cellular data, leaving families off the grid since early on Tuesday morning.

River levels in Tolaga Bay have reached record highs, surpassing levels during 1988's Cyclone Bola levels by more than 1m.

All roads in and out of Gisborne are closed.

A heavy rain warning remains in place for Tairāwhiti and strong wind gusts of 90km/h are possible from Tuesday evening.

Auckland

Ongoing wild weather is making it difficult to conduct a search and rescue for a missing firefighter in Muriwai.

One firefighter is missing and another is in critical condition after a house they were investigating collapsed.

Emergency services remain in Muriwai and helping evacuate residents who have been trapped by landslips and flooding.

About 200 people have fled their homes so far.

Refuge centres have been established at the local Surf Life Saving Club and Sand Dunez Beach Cafe. 

The nearby communities of Piha and Karekare have also been cut off with reports of widespread flooding and slips.

Meanwhile, the navy on Tuesday morning rushed toward a stricken ship near the Hen and Chicken Islands.

The vessel has been adrift at sea for more than 24 hours, with emergency services struggling to make contact with the sailor. However, the navy said the sailor has since been rescued.

There is a strong wind warning for Auckland with gusts reaching 120 km/h in exposed places on Tuesday afternoon and evening. 

Winds "are expected to produce widespread damage, especially to trees and powerlines and could lift roofs", MetService said.

"Transport and power networks are likely to be significantly impacted, with road closures and power outages.

"Conditions will be hazardous for motorists and there is a danger to life from flying debris and falling trees or branches."

Coromandel 

"Carnage" - that's how Thames-Coromandel officials describe the peninsula's state after Cyclone Gabrielle passed over the region. 

Local Civil Defence controller Gary Towler has told Newshub's Ashleigh Yates 95 percent of Coromandel's roads are closed due to severe flooding and slips.

"Overnight, the winds were howling [and] there were severe thunderstorms here in Whitianga," Yates told AM. "There is severe coastal erosion."

The Thames-Coromandel District Council has asked resident to conserve water for at least the new two days.

A strong wind warning remains in place for Coromandel, with severe gales forecast until at least midnight.

Hawke's Bay

Floodwaters have wrecked havoc on Hawke's Bay - with video showing raging torents where roads once were. 

On State Highway 50, near the Napier Golf Club, the road is no longer passable - with rapids streaming down. 

Cars have become stuck in the water and one man was seen trying to swim through floodwaters and rescue some one - before police officers advised him not to risk his own life.

Heavy rain was expected to ease in the region on Tuesday morning.

Weather: What you need to know about Cyclone Gabrielle right now
Photo credit: Newshub.

Northland

Evacuations took place in Northland's Mangawhare in Dargaville earlier on Tuesday morning after the nearby Awakino River breached its banks.

"With another high tide later today around 7pm, we are considering the potential future impacts and will provide advice for the community later this morning," Kaipara District Mayor Craig Jepson said. "In the meantime, we are asking anyone who has been evacuated to stay where they are and not to return home yet.

"There are multiple reports of roads flooded in low-lying areas in Dargaville and across the wider district."

Jepson said anyone in low-lying levels of Dargaville concerned about rising water levels should consider self-evacuation.

"For everyone else across Kaipara District, please stay home," he said in a statement. "Continue to avoid all non-essential travel while the wild weather continues.

"If you are in immediate danger, call 111. If you require welfare assistance due to Cyclone Gabrielle please contact 09 439 1111."

All of Northland remains under a red strong wind warning and a red heavy rain warnings is in place for western parts of the region south of Kaitaia.

Whangārei has been told to expect "damaging" 120km/h wind gusts on Tuesday.