Severe Weather Outlook

Issued: 9:42am Friday 22 Nov 2024

Valid Sunday 24-Nov-2024

A ridge of high pressure over the country is expected to move north during the day, and a front should move onto the lower South Island, bringing some rain to the west and south. Behind the front, strong west to southwest winds are expected.

There is low confidence of severe gale westerlies about Stewart Island and the southern coast of the South Island.

Valid Monday 25-Nov-2024

The ridge of high pressure lies slow-moving over the North Island. A front moves up the South Island while weakening.
There is minimal risk of severe weather.

Valid Tuesday 26-Nov-2024


The ridge of high pressure remains slow-moving over the North Island. A moist northwest flow develops over the lower South Island at night.
There is minimal risk of severe weather.

Valid Wednesday 27-Nov-2024

The ridge of high pressure remains slow-moving over the North Island, while a moist northwest flow strengthens over the lower South Island.

There is low confidence that rainfall accumulations could approach warning criteria over Fiordland. There is also low confidence that northwest gales could become severe over southern parts of Fiordland, Southland and Clutha.

Low confidence:

A 20% likelihood (or 1 chance in 5) of a warning being issued.

Moderate confidence:

A 40% likelihood (or 2 chances in 5) of a warning being issued.

High confidence:

a 60% likelihood (or 3 chances in 5) of a warning being issued.

New issues of this forecast are made available on this site at or before 16:30 NZST

Thunderstorm Outlook

Valid to Midnight Friday, 22-Nov-2024

Issued: 7:29am Friday 22 Nov 2024

No thunderstorms or significant convection expected during this period.



Valid to Noon Saturday, 23-Nov-2024

Issued: 7:14pm Friday 22 Nov 2024

No thunderstorms or significant convection expected during this period.



Valid to Midnight Saturday, 23-Nov-2024

Issued: 7:14pm Friday 22 Nov 2024

No thunderstorms or significant convection expected 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 25 millimetres per hour, or more.

Large hail:

Hailstones 20 millimetres in diameter, or larger.

Strong wind gusts (from thunderstorms):

Gusts of 110 kilometres per hour / 60 knots or stronger.

Damaging tornadoes:

Fujita F1 (wind speeds greater than 116 kilometres per hour / 63 knots) or stronger.