‘Unprecedented’ low snowfall forces Rainbow Ski Area to scrap season

Wednesday, 27 August 2025

A third South Island skifield has been forced to remain closed this winter, with Rainbow Ski Area calling its lack of snow “unprecedented”.

After months of weather extremes, the skifield near the Tasman village of St Arnaud confirmed on Wednesday morning it would not open at all this season.

The decision was the result of “unprecedented low snowfall to date in Nelson Lakes National Park”, ski area manager Marke Dickson said.

Just 29cm of natural snow had fallen since May 1, making it “one of the leanest winters” since Rainbow first opened in 1982, he said.

“There’s been no shortage of precipitation this year. But for skiers and snowboarders, it has been the wrong type.”

The announcement followed Temple Basin’s decision last week to abandon its season and Mt Cheeseman’s closure earlier this week – the first time it had not opened since World War II.

Rainbow Ski Area had planned to open on July 4. However, warm weather and repeated heavy rain, including storms that cut off St Arnaud and closed roads across the Tasman District, eroded the snow base despite extensive efforts by staff and volunteers.

Dickson said Rainbow planned for seasons like this.

“Running a mountain is not much different to farming or grape growing; you work hard to get ready for a bumper crop, but returns are always tied to the weather.

“Our job is to manage our way through the things we cannot control, ensuring that the club remains strong and ready for seasons to come.”

The skifield is operated by the Rainbow Sports Club, whose chairperson, Rachel Robinson, said it was not worth keeping the field in readiness for what might only have been “a few days” of skiing or snowboarding, which would take resources away from future years.

“The team did all they could to get our community on snow this season,” she said.

“We’ve had many more great winters than poor ones, so volunteers and supporters can look forward to 2026 with confidence.”

Season pass holders and those with three-day lift tickets would have their passes automatically rolled over until 2026.

The club said it would now focus on improvements ahead of reopening in mid-July 2026.

NIWA has confirmed the Upper South Island is experiencing one of its lowest snowfall years on record, with unprecedented low snow levels at two key alpine monitoring sites.

Dr Jono Conway, hydrological forecasting scientist at NIWA, said snow depth at Mahanga, in the Nelson Lakes area at 1940 metres, was currently the second lowest recorded since monitoring began in 2008.

Only 2011 was lower, he said.

At Mt Philistine, near Arthur’s Pass at 1650 metres, sensors were recording zero snow — something never previously observed in records dating back to 2010.

Conway said reliable long-term snow depth data only went back to the early 2000s.

But, warming of about 1C over the past century reduced the odds of snowfall, particularly at moderate elevations that often saw both snow and rain.

NIWA modelling also showed the 1990s were significantly snowier than more recent decades.

While he wouldn’t want to speculate on the viability of skifields, by mid-century they would expect an average season to include more rain and less snow at all elevations.

He warned that warmer, wetter winters were a consistent climate projection: “Warm rain is snow’s worst enemy ‒ one day of warm rain can melt a lot of snow.”

MetService meteorologist Mmathapelo Makgabutlane said the season “started off promising”, but recent weather systems had brought “a lot of rain to the top of the South Island” rather than snow.

Many of the systems were northerly flows, which were too warm to produce good snow in the Nelson Lakes area.

Another common pattern ‒ cold southerlies near the surface with warmer northerly air higher up ‒ had delivered snow elsewhere in the country, but Nelson Lakes was “too sheltered from significant snow from this direction.”

“The type of weather pattern that is more favourable for snow to get into the Nelson Lakes area is cold westerlies bringing snow, which we have not had much of this season,” she said.

Makgabutlane said ski fields themselves were best placed to compare snowfall amounts against previous years, but climate drivers such as the Southern Annular Mode were also likely to have played a role.

“The story is still unfolding,” she said.

James Renwick, weather and climate researcher, said it was largely natural variability.

“Just the way things play out some years.”“But, climate change is acting to reduce the chances of good snow years over time, so the chances of years like this one are increasing all the time.”