Thunderstorm Outlook
Issued at 8:01am 9/07/2026
Valid from 8:01am 9/07/2026 to Midnight 9/07/2026
A moist southerly flow brings rain to the east of the North Island. There is a low risk of thunderstorms with heavy rain for the east of the Wairoa District, and the east of Gisborne as indicated on the chart. Note that there is a moderate risk of thunderstorms off the coast of Gisborne and Bay of Plenty as indicated. There is minimal risk of thunderstorms or significant convection elsewhere during this period.
Issued at 9:55am 9/07/2026
Valid from Midnight 9/07/2026 to Midday 10/07/2026
The risk of thunderstorms over land is minimal Friday morning, but there is a low risk off the coast of Gisborne and Bay of Plenty as indicated on the chart.
Issued at 9:10am 9/07/2026
Valid from Midday 10/07/2026 to Midnight 10/07/2026
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.
