Severe Weather Outlook

Issued: 9:36am Wednesday 26 Mar 2025

Valid Friday 28-Mar-2025

A cold front moves across the North Island bringing scattered rain. A ridge of high pressure builds across the South Island.

There is minimal risk of severe weather.

Valid Saturday 29-Mar-2025

A ridge of high pressure covers central New Zealand. A moist easterly flow brings rain or showers to northern New Zealand.

There is minimal risk of severe weather.

Valid Sunday 30-Mar-2025

A ridge of high pressure across central New Zealand weakens. A front moves onto the lower South Island, bringing rain. A southeast flow affects northern New Zealand.

There is minimal risk of severe weather.

Valid Monday 31-Mar-2025

A front becomes slow-moving over the lower South Island, bringing further rain to parts of Fiordland and southern Westland. A southeast flow covers the North Island.

There is minimal risk of severe weather.

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 Thursday, 27-Mar-2025

Issued: 8:21pm Wednesday 26 Mar 2025

The front moves slowly northwards during the second half of Thursday, and there is an associated low risk of thunderstorms in the Westland and Grey districts in the afternoon and evening, and in Buller during the evening. No thunderstorms or significant convection expected elsewhere 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.