Thunderstorm Outlook
Issued at 7:58am 3/06/2026
Valid from 7:58am 3/06/2026 to Midnight 3/06/2026
Shallow low is forecast to move east over the waters to the north of Bay of Plenty, allowing a moderate risk of thunderstorms about eastern Bay of Plenty north of about the Motu River, including parts of Gisborne/Tairawhiti east of Te Araroa this morning and afternoon with associated heavy rain of 10 to 25mm per hour. In addition, there is a broader low risk about and east of Whakatane, including the ranges of Gisborne/Tairawhiti. There is minimal risk of thunderstorms or significant convection elsewhere in New Zealand during this period.
Issued at 7:42pm 3/06/2026
Valid from Midnight 3/06/2026 to Midday 4/06/2026
An unstable north to northwest flow spreads over the country during Thursday morning, with a front forecast to reach western parts of both islands late morning. This front brings a moderate risk of thunderstorms to mainly coastal parts of the West Coast and Fiordland, excluding the Grey District, after dawn, with associated heavy rain of 10 to 25 mm per hour possible, as depicted on the chart. There is a low risk of thunderstorms for Taranaki north of Eltham, Tasman west of Motueka, and the remainder of the West Coast and Fiordland including the Southern Alps, as drawn on the chart. There is minimal risk of thunderstorms or significant convection elsewhere in New Zealand during Thursday morning.
Issued at 10:12am 3/06/2026
Valid from Midday 4/06/2026 to Midnight 4/06/2026
The front is forecast to move southeast over the South Island and lower North Island during the afternoon, but lingering about the central North Island. Embedded troughs follow this front affecting the South Island, the most notable approaching late in the day. There is a moderate risk of thunderstorms in proximity to the slow moving front about Taranaki north of Eltham and coastal parts of Waitomo, with heavy rain of 10 to 25mm per hour, possibly more. In addition, a moderate risk remains for the coastal parts of the West Coast from Farewell Spit through to the fiords, with heavy rain of 10 to 25mm per hour possible. A broader region of heavy showers is expected to affect western and northern parts of both islands, with a low risk of thunderstorms as indicated on the chart. There is minimal risk of thunderstorms or significant convection elsewhere in New Zealand 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.
