Severe Weather Warnings and Watches

Issued by MetService at 10:05am Saturday 24 May 2025

Heavy rain and strong northwest winds expected to affect parts of the South Island

A front sweeps over the South Island from the Tasman Sea during Sunday and Monday, bringing a period of heavy rain and strong north to northwest winds.

Warnings and Watches are in force for heavy rain and severe gales.

Please keep up to date with the latest forecasts.

Heavy Rain Warning - Orange

Area: Headwaters of the Canterbury lakes and rivers about and south of Arthur's Pass

Period: 12hrs from 5:00pm Sunday 25 May 2025 to 5:00am Monday 26 May 2025

Forecast: Expect 140 to 170 mm of rain about the main divide, and 80 to 110 mm within 15km farther east. Peak rates of 20 to 30mm/h expected Sunday night and early Monday morning about the divide. Thunderstorms possible from Sunday night. Freezing level 3200 metres lowering to 2400 metres.
Minimal chance of upgrading to a Red Warning.

Impact: Streams and rivers may rise rapidly. Surface flooding, slips, and difficult driving conditions possible.

Action: Clear your drains and gutters to prepare for heavy rain. Avoid low-lying areas and drive cautiously.

Area: Headwaters of the Otago lakes and rivers

Period: 12hrs from 2:00pm Sunday 25 May 2025 to 2:00am Monday 26 May 2025

Forecast: Expect 80 to 100 mm of rain about the main divide, and 70 to 90 mm within 15km farther east. Peak rates of 15 to 25mm/h expected. Thunderstorms possible Sunday night. Freezing level 3200 metres lowering to 2400 metres.
Minimal chance of upgrading to a Red Warning.

Impact: Streams and rivers may rise rapidly. Surface flooding, slips, and difficult driving conditions possible.

Action: Clear your drains and gutters to prepare for heavy rain. Avoid low-lying areas and drive cautiously.

Area: The ranges of Westland

Period: 16hrs from 2:00pm Sunday 25 May 2025 to 6:00am Monday 26 May 2025

Forecast: Expect 150 to 190 mm of rain. Peak rates of 20 to 30 mm/h expected Sunday night and early Monday morning. Thunderstorms possible.
Minimal chance of upgrading to a Red Warning.

Impact: Streams and rivers may rise rapidly. Surface flooding, slips, and difficult driving conditions possible.

Action: Clear your drains and gutters to prepare for heavy rain. Avoid low-lying areas and drive cautiously.

Heavy Rain Watch - Yellow

Area: The ranges of Grey and Buller

Period: 12hrs from 9:00pm Sunday 25 May 2025 to 9:00am Monday 26 May 2025

Forecast: Periods of heavy rain, and amounts may approach warning criteria.
Moderate chance of upgrading to a Warning.

Strong Wind Watch - Yellow

Area: Canterbury High Country north of Mt Cook, and Marlborough south of Ward

Period: 12hrs from 6:00pm Sunday 25 May 2025 to 6:00am Monday 26 May 2025

Forecast: Northwest winds may approach severe gale in exposed places.
Moderate chance of upgrading to a Warning.

An update for severe weather will be issued by: 9:00pm Saturday 24 May 2025

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Action advice supplied by the National Emergency Management Agency.

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