Southland Boys' High School players celebrate their historic win. Photo: Getty Images

The weather has rained on Southland Boys' High School's victory parade.

Invercargill was due to celebrate SBHS's National First XV Championship with a parade through the city tomorrow but it has been cancelled because of "temperamental weather".

Great South chief executive Chami Abeysinghe said a blustery and wet forecast had put a dampener on the planned celebrations, and the difficult decision had been made to cancel. 

"It’s unfortunate we’re not able to proceed with this celebration. It would have brought real vibrancy to the central city, but the weather isn’t playing the game."

Southland Boys' High School came from behind to beat Westlake Boys' and take out the prestigious Moascar Cup, winning their school’s first-ever national rugby title in its more than 100-year history. 

Invercargill Mayor Nobby Clark said he was still looking forward to welcoming the boys to a reception at the council tomorrow to honour the win.

"As a city and as a province, we’re incredibly proud of what the boys have achieved on the national stage," Mr Clark said. 

Southland Boys’ High School principal Simon Coe said it was a shame the weather had cancelled the parade – but the accomplishments of the team would be a lasting memory regardless.

"The team is humbled by the support and well wishes they’ve received since their win," he said.

"The memory of how the whole province celebrated their achievements will remain with these boys for a lifetime. Now, at a crucial time in their studies, it’s back to normality and time to focus on exams."