Severe Weather Outlook
Issued: 1:57pm Sunday 31 Aug 2025
Valid Tuesday 02-Sep-2025
The front also brings significant snow down to 5 to 600 metres over the south of the South Island. While warning amounts are unlikely to accumulate there could be significant disruptions to travel due to snow on roads. Livestock may also be affected by the snow and cold temperatures.
Valid Wednesday 03-Sep-2025
The risk of severe weather is considered minimal.
Valid Thursday 04-Sep-2025
Valid Friday 05-Sep-2025
The risk of severe weather is considered minimal.
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 Monday, 01-Sep-2025
Issued: 8:02pm Sunday 31 Aug 2025
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.