Thunderstorm Outlook
Issued at 2:42pm 16/10/2026
Valid from 2:42pm 16/10/2026 to 1:00am 17/10/2026
Unstable south to southwesterlies bring a low risk of thunderstorms to parts of Gisborne/Tairawhiti this afternoon. A combination of wind convergence and cold temperatures in the upper atmosphere bring a low risk of thunderstorms to parts of the upper North Island this afternoon and early evening as depicted on the chart, and there is a moderate risk of thunderstorms this afternoon for Coromandel Peninsula, southeastern parts of Auckland, and Great Barrier Island, with brief heavy rain and small hail possible. There is minimal risk of thunderstorms or significant convection elsewhere today.
Issued at 7:42pm 16/10/2026
Valid from 1:00am 17/10/2026 to 1:00pm 17/10/2026
There is minimal risk of thunderstorms or significant convection during this period.
Issued at 8:55am 16/10/2026
Valid from 1:00pm 17/10/2026 to 1:00am 18/10/2026
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.
