Thunderstorm Outlook
Issued at 8:03am 5/11/2026
Valid from 8:03am 5/11/2026 to 1:00am 6/11/2026
Daytime heating is expected to generate convective showers across parts of the North Island today, and there is a broad low risk area of thunderstorms during the afternoon and evening as indicated on the chart. Within this, there is a moderate risk of thunderstorms about southern Northland, as well as eastern Taumarunui, and Taupo to the Tararua District, with localised heavy rain of 10-25 mm/h. There is minimal risk of thunderstorms or significant convection elsewhere during this period.
Issued at 10:28am 5/11/2026
Valid from 1:00am 6/11/2026 to 1:00pm 6/11/2026
A front moves onto the country from the west during Friday morning, bringing a low risk of thunderstorms about the west coast of the South Island from Hokitika northwards before dawn, and about northern and western Northland later in the morning. There is minimal risk of thunderstorms or significant convection elsewhere during this period.
Issued at 10:35am 5/11/2026
Valid from 1:00pm 6/11/2026 to 1:00am 7/11/2026
A warm airmass over central and northern New Zealand brings unstable showery conditions through the second half of Friday. There is a moderate risk of thunderstorms and heavy rain of 10-25 mm/h extending from Northland to parts of Hawke's Bay during the afternoon and evening, as indicated on the chart. In addition, there is a low risk of SEVERE thunderstorms for nld and Auckland during the afternoon and evening, bringing localised downpours of 25-40 mm/h. A broader area with a low risk of thunderstorms covers the North Island from Manawatu and the Tararua District northwards through the entire period. At night there is a low risk of downpours producing 25-40 mm/h for northern Northland, with a front approaching from the west. Over the South Island, there is a low risk of thunderstorms with afternoon and evening convection about the Nelson Lakes and Kahurangi National Parks. Another low risk of thunderstorms covers Clutha and southern Dunedin with a southwest change that moves through during the afternoon and evening. There is minimal risk of thunderstorms or significant convection elsewhere during this period.
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.
