Thunderstorm Outlook
Issued at 8:16am 11/10/2026
Valid from 8:16am 11/10/2026 to 1:00am 12/10/2026
A weak front moves over the northwest of the North Island this morning, then a combination of afternoon and early evening wind convergence and cold air in the upper atmosphere is expected to bring heavy showers to the east of the North Island. There is a low risk of thunderstorms for much of the North Island from Waikato and Coromandel Peninsula southwards, excluding Horowhenua to Wellington as depicted on the chart. However, for a time this afternoon, the risk of thunderstorms is considered moderate over Gisborne/Tairawhiti, Hawke's Bay, northern Manawatu and the Tararua District. These thunderstorms may produce localised rainfall rates of 10 to 20 mm per hour and hail of 5 to 15 mm diameter. There is minimal risk of thunderstorms or significant convection elsewhere during this period.
Issued at 9:29am 11/10/2026
Valid from 1:00am 12/10/2026 to 1:00pm 12/10/2026
There is minimal risk of thunderstorms or significant convection 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.
