MetService said there was uncertainty about where the cyclone would track from then.
Meteorologists have warned the tropical cyclone, which is likely to form in the Coral Sea between New Caledonia and Australia within a day, could unleash a month’s worth of rain in just days.
Forecaster Niwa said high ocean temperatures along Cyclone Gabrielle’s initial track are offering energy toward a fast intensification.
Forecaster Hauraki Gulf Weather said a synoptic scale rotation is now quite evident on the sat loop as it continues to track over the Coral Sea.
MetService have put out fresh reminders of what the cyclone could mean for areas that are affected by it, including how strong winds can damage trees, powerlines and unsecured structures.
Strong winds could also make driving conditions hazardous, especially for high-sided vehicles and motorcycles.
Heavy rain has the potential to make streams and rivers rise rapidly, cause surface flooding and slips and also make driving conditions hazardous.
Auckland Emergency Management (AEM) controller Rachel Kelleher said there would be a “settled run” of weather in the city this week.
She said people should use this break in the weather to clean up from last week’s flooding and prepare for possible severe weather this weekend.
Niwa meteorologist Ben Noll said the storm would be more than an average low-pressure system and would be “quite impactful”.
“It’s going to come pretty close to New Zealand, now in terms of the exact track, say just to the west of the North Island or just to the east of the North Island.
“That’s the kind of detail that is going to be refined in the coming days and that detail will actually mean a lot as to which regions see the most hazardous weather,” said Noll.
“I would describe it as above-average confidence that the system will move into the New Zealand region.”
Noll said the country, especially flood-ravaged regions such as Auckland, Northland and the Coromandel, could be dealing with a large amount of rain given the system has emerged in the tropics.
“When you’re talking about a system that was once in the tropics you could be talking about a month’s worth of rain or more. That does depend on the forward speed, how fast the system is moving and what part of the country it moves into,” he said.
Noll said there is potential for powerful winds strong enough to do damage.
He also said the storm would cause rough seas despite whether it would track over the country or not.
MetService meteorologist Peter Little said the cyclone would “absolutely” head towards New Zealand but also said it was too early to say if it would track over the country or if it would be further away.
Various weather models currently show that the cyclone’s centre will track over the top of the North Island.
“The system is expected to track southeastwards, there are some differences in how quickly it is brought southeastwards and whether it will be near the country or whether it will be a little bit further away but certainly there is a risk of further heavy rain for northern parts of the country from very late on Sunday into Tuesday,” said Little.
“We’re monitoring very closely obviously because even a small amount of rain for some of the areas recently hit by flooding could cause problems.”
Those in the affected areas are being urged to prepare. Read more about it here.
Little said even a small change in the cyclone’s position or intensity over the next few days would have a large impact on where the system would end up.
“A very small change in the next couple of days could end up with a different picture,” he said.
Meanwhile, Hauraki Gulf Weather tweeted that the storm could be historic if it were to form and said it would bring dangerous winds with it.
“All main global models apart from the Chinese brings a strong extra-tropical cyclone into the upper North Island late Monday. With over five days out, things can still change, so this is still early guidance but the trend remains concerning,” said the forecaster.
