Severe Weather Outlook

Issued: 10:42am Friday 14 Aug 2026

Valid Sunday 16-Aug-2026

The low moves slowly away to the east of the North Island leaving a strong southerly flow over the Island. Rain or showers affect many areas, especially in the east.

There is moderate confidence that rainfall accumulations will meet warning criteria over the Wairoa District and about Gisborne/Tairawhiti south of Gisborne city throughout the day. There is low confidence that a heavy rain warning will be required for Wairarapa during the morning.

In addition, there is low confidence that a warning will be required for severe south to southeast gales about the Marlborough Sounds, Wellington, Kapiti Coast and southern and western Taranaki during the morning and afternoon. There is also low confidence of severe southeast gales for the ranges of northern Hawke's Bay and Gisborne/Tairawhiti, and also about eastern Bay of Plenty from midday onwards.

Valid Monday 17-Aug-2026

A south to southwest flow covers New Zealand, strong over the North Island at first, bringing rain or showers to southern and eastern areas of the country.

There is moderate confidence that a heavy rain warning will be required for the Wairoa District and about Gisborne/Tairawhiti south of Gisborne city during the morning.

In addition, there is low confidence of severe southeast gales for the ranges of northern Hawke's Bay and Gisborne/Tairawhiti, and also about eastern Bay of Plenty during the morning.

Valid Tuesday 18-Aug-2026

A south to southwest flow over New Zealand eases as a ridge of high pressure extends onto southern and western parts of the country.

There is minimal risk of severe weather.

Valid Wednesday 19-Aug-2026

The ridge of high pressure extends onto all of New Zealand and builds.

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 Friday, 14-Aug-2026

Issued: 8:24am Friday 14 Aug 2026

A low near Northland is moving slowly southeast. Fronts associated with the low are bringing rain to Northland, Bay of Plenty and northern Gisborne/Tairawhiti. There is a moderate risk of thunderstorms about eastern Bay of Plenty and northern Gisborne/Tairawhiti this morning and afternoon. These thunderstorms may bring localised heavy rain with intensities of 10 to 25 mm per hour and there is a low risk of downpours of 25 to 40 mm per hour. A low risk of thunderstorms exists until tonight over the whole Bay of Plenty region and south of the moderate risk area in Gisborne/Tairawhiti. For Northland, there is a low risk thunderstorms until tonight, with a low risk of localised downpours this morning and afternoon. About inland Taranaki and east to about Ohakune, there is a low risk of thunderstorms this afternoon. Elsewhere, the risk of severe convection or thunderstorms is minimal.



Valid to Noon Saturday, 15-Aug-2026

Issued: 10:16am Friday 14 Aug 2026

A large low over the North Island slowly moves off to the east. There is a low risk of thunderstorms about Gisborne/Tairawhiti north of Gisborne City during the morning. Elsewhere, the risk of severe convection or thunderstorms is minimal.



Valid to Midnight Saturday, 15-Aug-2026

Issued: 10:21am Friday 14 Aug 2026

The low continues to move away to the east. Showers are likely to develop about Waikato, Waitomo and Taumarunui during the afternoon and there is a low risk of thunderstorms in these areas during the afternoon and evening. Elsewhere, there is minimal risk of severe convection or thunderstorms.



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.