We are closely monitoring Cyclone Vaianu as it transitions into New Zealand waters. Current modeling suggests the system will begin impacting the upper North Island early Sunday, with the heaviest rain and surge expected throughout Sunday, April 12.
We’re also chasing Cyclone Vaianu to bring you the latest developments. Keep it locked here for regular updates and breaking footage from the ground.
Always refer to MetService for official warnings.
[10/04 /26 – 10 am NZST] – Vaianu has now transformed into a powerful extra-tropical system, with its outer spiral rainbands beginning to impact the upper NI. The models are still a wee bit out of whack and a nudge east or west could dramatically change how hard and where the worst hits. MetService has issued a multiple rain/wind warnings, with a RED WARNING issued for the Coromandel.
Tracking
Models are largely in sync, however have slightly east/west deviations. ECMWF has the eye crossing just west of Great Barrier Island and tracking down the Firth of Thames at around 9am Sunday.
ECMWF Track
Rainfall & Flood Risk
While Vaianu won’t see the staggering rainfall totals of Gabrielle due to its speed, the intensity remains high. The Coromandel, Waikato, Bay of Plenty, Taranaki and Gisborne are the primary targets. The Ruahines may also receive heavy rainfall.
Up to 200mm is expected.
Because the system is fast moving, this rain will fall in a concentrated burst, significantly increasing the risk of flash flooding.
The storm’s speed is dictated by a classic pressure squeeze. A powerful high pressure system to the east is acting as an atmospheric wall, forcing the cyclone into a narrow corridor. This intense pressure gradient effectively slingshots the system southward, limiting the duration of the impact but potentially intensifying the conditions.
Wind
The wind gusts will be strongest across the Coromandel, Bay of Plenty, and Gisborne. Another area of concern is the West Coast around the Kaipara Harbour area. Residents should prepare for damaging gusts exceeding 150km/h, capable of causing widespread power outages and structural damage.
