A tropical cyclone likely to emerge this weekend near the Coral Sea could intensify into a Category 5 storm as it heads south towards New Zealand, Weatherwatch says.
All eyes are on the tropical depression currently sitting around the Solomon Islands that is expected to turn into a tropical cyclone by Sunday as it moves towards New Caledonia.
By Tuesday, WeatherWatch says the cyclone could be as strong as a Cateogry 5, but is more likely to be either Category 4 or 3.
"That's a severe storm," forecaster Philip Duncan says. "So New Caledonia, for two or three days now, has been showing a direct hit. The French nation [is] watching it very closely. Vanuatu right on the outer edges of it, Norfolk Island very close."
At this point on Tuesday, WeatherWatch expects rain to be pouring across New Zealand. The forecaster says this is linked to the cyclone.
"Even if the storm stays offshore, it is still going to help encourage a very humid tropical airflow across the country. We're definitely going to get some rain next week. Whether or not the cyclone is going to directly hit us, that still remains unknown."
On Wednesday, the storm is forecast to be in the "950 hectopascal range".
"So it is still strengthening. That's why we're saying category five is possible. Heavy rain downpours in the North Island. Absolutely classic La Niña summer day on Wednesday next week. Lots of rain around, lots of downpours, a lot of humidity, 100 percent humidity in places and it is from the very north to the very south that you get that."
As the waters get cooler from New Caledonia to New Zealand, the system will weaken. However, WeatherWatch says the sea surface temperatures around northern Aotearoa are warmer than average in the low 20s, meaning it "may retain a fair amount of energy".
Two models shown by Weatherwatch both show the cyclone moves north to northeast of New Zealand by the middle of next week.
"Very close call to New Zealand but it could still directly impact us. It might still go further out to sea but either way, I think we're gonna get a fair amount of humidity, rain and cloud next week."
Duncan says WeatherWatch is forecasting a 60 percent chance of the cyclone "impacting our weather".
MetService is also watching the cyclone. It notes there is a "high risk" the weather system will become a tropical cyclone over the Coral Sea on Saturday and then move southeast.
