Cyclone Cody is expected to pass east of New Zealand later today, with the latest guidance that it won't make land but some effects will still be felt.
The potential impact of Cody has been significantly downgraded from several days ago when it was feared the storm could brush past or even hit the East Cape.
MetService said this morning the cyclone was currently over waters to the northeast, and was expected to pass far east of the East Cape on Monday as it heads southwards, before moving further south towards the Chatham Islands on Tuesday.
"The risk of heavy rain has diminished as the system tracks well east of New Zealand. However, the risk of severe gales about exposed parts of eastern Bay of Plenty and Gisborne remain," the forecaster said.
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Hazardous conditions were still expected about the exposed eastern coastlines of the North Island, where large easterly swells, significant sea surges and rips and coastal inundation were possible.
Last night parts of Northland's east coast were hit by huge waves that caused significant damage at Tutukaka Marina. Civil Defence Northland said it believed the waves may have been created by the combined effect of Cyclone Cody and a huge volcanic eruption in Tonga last night.
It has warned people on the east coast to stay away from the water today as strong, frequent surges were continuing and surges could hit previously calm areas.
MetService this morning said there was still a strong wind watch in place for Bay of Plenty east of Ōpōtiki and Gisborne north of Tolaga Bay, valid from 3am Monday to 12am Tuesday.
But a heavy rain watch for Gisborne and the Wairoa District has been lifted as heavy rain is no longer expected.
Gisborne Civil Defence emergency manager Ben Green said on Saturday they want to be prepared for any scenario.
"We're probably as well set up as we can be going into what's hopefully potentially just a glance of the system coming through."
Green said they had been doing courtesy calls to make sure people in remote areas of the region are aware gale-force winds, intense rain and high seas were likely.
He said they were treating it as a worst-case scenario, particularly with people holidaying in remote coastal areas.
River levels are being monitored and there's been additional cleaning of sewers and stormwater pipes, he said.
The transport agency, Waka Kotahi, said people should be prepared for large swells on low-lying coastal roads, as well as heavy rain and severe gales.
This kind of weather can cause slips, with debris and trees falling on the roads.
Waka Kotahi's national journey manager, Helen Harris, said high-sided vehicles need to be particularly cautious in those types of conditions.
She said drivers of high-sided vehicles should consider not travelling until the severe weather dies down, even if the roads are open.
Crews will be monitoring the situation closely and will close roads if the weather gets too dangerous.
Surf Life Saving Northern Region (SLSNR) is also urging the beach-going public to take much greater care on northeastern beaches and prepare for closures as category 1 Tropical Cyclone Cody nears.
Northland's patrolled surf beaches are at Ocean Beach, Whangārei Heads, Waipū Cove, Ruakākā, and Mangawhai Heads on the east coast and Ahipara and Baylys Beach on the west coast.
SLSNR lifesaving operations manager James Lea is warning beachgoers and holiday-makers to remain vigilant as large waves and strong rip currents create dangerous swimming conditions.
"With forecasted strong winds and a lot of energy pushing into eastern beaches this weekend, it will be extremely important to maintain your safety and safety of others this weekend. Strong surf and large waves will create strong currents," Lea said.
"There will be a lot of water moving which would easily knock you off your feet. Keep a close eye on young children – be able to reach them quickly, see them at all times and stay well away from the water.
"We also ask that storm-spectators and rock-fishers take extra care if spending any time on the rocks this weekend. Large swells can easily knock you off and into the dangerous water.