Updated 9.40 am

Flooding possible, heavy rain and snow for parts of South

Metservice is urging Dunedin residents to be prepared for possible flooding over Labour Weekend, as a large area of low pressure looks to drop more heavy rain along coastal Otago.

Meteorologist Clare O’Connor said a large area of low pressure was expected to cover the South Island tomorrow, and heavy rain or showers were likely to affect many areas, with snow about the South Island high country.

Heavy easterly or southeasterly rain was likely to fall about eastern South Island areas, from Canterbury to northern and eastern parts of Otago - including Dunedin.

It was also possible that easterly rain could reach warning criteria about southern Otago, Clutha, inland Southland and eastern Fiordland.

"There is a risk of some heavier falls of rain around there on Saturday, which could extend into Sunday as well," Ms O'Connor said.

"There’s a low that will form to the west, just off Fiordland, and that will push the weather eastward before pulling it all back around on to the southeast coast of the South Island.

"It’s difficult to say how much rain will fall at this stage, but given that your soil conditions down there are already saturated from recent rain, there may be more flooding."

Heavy rain warnings may be issued this morning, and she urged people to keep up to date with the forecasts, she said.

It'll be fine on Friday driving the Milford Road but heavy rain and snow is forecast for the...
It'll be fine on Friday driving the Milford Road but heavy rain and snow is forecast for the weekend, including Monday. PHOTO: MILFORD ROAD ALLIANCE

Care needed on Milford Road

The Milford Road in Southland reopened at 10am today after being closed since noon Wednesday due to a heightened risk of avalanche.

Though the avalanche risk is now low, care is needed  on State Highway 94 at the weekend, Milford Road Alliance advised.

"Forecasts are now indicating more snow than initially expected, down to 600 metres. Travel disruptions likely on Saturday from mid-morning."

Though today would be fine, heavy rain and snow were set to affect the area from tomorrow until Monday. 

Heavy snow warning 

Meanwhile, there is a high confidence that a heavy snow warning would be issued for the Canterbury High Country, the Southern Alps and the Westland ranges for heavy snowfalls above about 500m.

It was also possible snowfall could affect parts of inland Otago and a heavy snow warning may be required for snow above 500m.

On Sunday, the large area of low pressure was expected to remain over the South Island, and it was possible the heavy rain would continue to affect South Canterbury and eastern Otago on Sunday, requiring a further heavy rain warning.

By Monday, the low should have weakened and moved out east of New Zealand, leaving much of Otago and Southland with showers and light winds.

Ms O’Connor said if people were travelling out of town this weekend, they should drive to the conditions, allow extra time to get there, avoid travelling at night, and watch for surface flooding, slips and fallen trees or branches.

"Also, before you leave home, make sure your house is prepared for heavy rainfall.

"Make sure your drains and gutters are clear, and make sure your house is ready for severe weather."

john.lewis@odt.co.nz