Tasman braces for up to 600 millimetres of rain over the long weekend as MetService issues fresh South Island warnings

MetService has issued heavy rain warnings across parts of the South Island for the King’s Birthday long weekend, with the Tasman district expecting up to 600 millimetres of rain in higher peaks by Tuesday and a moderate chance of the warning being upgraded to a red alert.

Orange warnings come into effect from Sunday morning for Tasman, Buller, Westland and the Richmond Ranges, according to MetService. More than 300 millimetres of rain is forecast for parts of the West Coast and Tasman, with flooding, slips and dangerous driving conditions all possible, and further warnings are expected to be issued for the central and northern North Island early next week.

MetService forecaster Gerard Bellam said Tasman would bear the brunt of the system. “We’re expecting 350 to 450mm but we might see as much as 600mm about some of the higher peaks there,” he told RNZ. “And the other point is that we have a moderate chance of this warning area being upgraded to a red warning.”

Tasman Mayor Tim King said he was not expecting dramatic flooding but warned that rivers would rise quickly over the weekend. “What we are requesting is given it’s a long weekend, given lots of people are likely to be travelling both around the district and in and out of it, just to bear in mind, keep an eye on the weather, keep an eye on the forecast and council information,” he said.

Westland Mayor Helen Lash said she was hopeful the rainfall would be manageable because it was forecast to fall over a longer period rather than in a sudden burst. “This sort of rainfall has the ability to put us through the alarm bells, no two ways about that, but it just depends on that level of rain coming over a longer period of time that will be what saves us at this stage,” she said.

Northland is set to be under a heavy rain watch from late Monday until Tuesday, while the headwaters of the Otago lakes and rivers are also under a heavy rain watch and the Canterbury High Country is under a strong wind watch.

The new warnings land less than a year on from two devastating floods that hit the Tasman district in June and July 2025, including a one in a hundred year event that destroyed homes and livelihoods around the Motueka catchment. The repair bill came in close to 50 million dollars, with about three quarters covered by insurance payouts or government contributions and 12 million dollars in costs to the Tasman District Council.

That recent memory has been driving a hands on community response. The Motueka Catchment Collective held an interactive workshop in Tapawera this week, drawing about 100 residents from across the 2000 square kilometre catchment to share experience, knowledge and ideas for managing flood risk. The group was formed six years ago by farmers who wanted to look after the health of the region’s rivers, and told RNZ the community kept asking for more education around flood risk management.

Dana Carter, who speaks for the collective, said last year’s floods had been a turning point. “There’s been a bit of work since then to try and just prepare moving forward so that people are more resilient to cope with these sorts of events,” she said. The group is now looking across forestry, farming and urban settings at land use changes that can reduce flood impacts, from fencing waterways and wetlands to large scale planting.

Tapawera resident Sarah Jacobs, who was evacuated with only the clothes on her back during last year’s floods and spent four days without her belongings or medication, said the experience had left her with post traumatic stress that flared up every time a rain warning came through. “I’m lying there listening to the rain on the roof and I’m a very, very positive, stoic, strong woman but that goes out the window when you’re listening to that rain on the roof,” she said. She has since joined her local civil defence planning team to help with community preparedness.

Della Webby of Tapawera Connect said recovery had taken far longer than expected and she was still supporting around 20 affected residents, including a family still out of their home and farmers dealing with fences down and crops lost. The workshop, she said, came at a useful moment as people processed the last event and looked ahead to the next.

Earth Sciences principal hazards scientist Emily Lane told RNZ the Motueka River had flooded for the last 150 years and would continue to do so, with increasing frequency that scientists attribute to climate change. She pointed to the 1877 flood, which descriptions suggest was comparable to Cyclone Gabrielle, and to four major floods inside two months in 1929. University of Waikato professor Holly Thorpe has separately documented growing levels of “rain anxiety” among people in repeatedly flooded communities.

For travellers over the long weekend, the advice is simple. Check the forecast before setting off, allow more time on the road, and turn back if conditions deteriorate. The warning area covers some of the most popular driving routes between Nelson and the West Coast, including State Highway 6 through Buller and the Lewis Pass road into North Canterbury.

How are you preparing for the wet weekend, and what is your community doing to build resilience after last year’s storms? Leave a comment below and join the conversation.

This article was written by AI, briefed to report the facts, hopefully without some of the bias people bring to the job 🙂