Thunderstorm Outlook
Issued at 6:58am 10/04/2026
Valid from 6:58am 10/04/2026 to Midnight 10/04/2026
There is minimal risk of thunderstorms or significant convection during this period. A front extends from the northern North Island to the Chatham Islands and is moving slowly eastwards in the south. There is minimal risk of thunderstorms over mainland New Zealand, but for the Chatham Islands, there is a low risk of thunderstorms this morning and early afternoon.
Issued at 8:01pm 10/04/2026
Valid from Midnight 10/04/2026 to Midday 11/04/2026
There is minimal risk of thunderstorms or significant convection during this period. A front extends from the northern North Island to the Chatham Islands and is moving slowly eastwards in the south. There is minimal risk of thunderstorms over mainland New Zealand, but for the Chatham Islands, there is a low risk of thunderstorms this morning and early afternoon.
Issued at 10:14am 10/04/2026
Valid from Midday 11/04/2026 to Midnight 11/04/2026
Cyclone Vaianu is expected to be approaching the northern North Island Saturday evening. There are many Watches and Warnings in place for severe gale winds and and heavy rain - refer to https://www.metservice.com/warnings/home for more details. A rainband south of the cyclone is expected to affect Gisborne/Tairawhiti and Mahia Peninsula from the afternoon and there is a low risk of thunderstorms producing heavy rain. A low risk of thunderstorms develops about eastern Northland, north of Whangarei in the evening. Elsewhere, the risk of severe convection or thunderstorms is minimal.
Severe Thunderstorm Criteria
In New Zealand, MetService classifies a thunderstorm as severe if one or more of the following criteria are met:
Heavy rain (from thunderstorms):
Rainfall of 25mm/h, or more.
Large hail:
Hailstones 20mm in diameter, or larger.
Strong wind gusts (from thunderstorms):
Gusts of 110km/h (60 knots) or stronger.
Damaging tornadoes:
Fujita F1 - i.e. wind speeds greater than 116km/h (63 knots) or stronger.
Note: some tornadic systems such as funnel clouds, waterspouts and small land-based tornadoes are possible with thunderstorms that may not be classified as severe.
