• - Forecasters warn Southland residents of surface flooding, slips and dangerous conditions due to heavy rain.
• - MetService expects up to160mm of rain in Southland, Westland, and parts of Otago.-
• - Strong winds and snow are also forecast for the South Island and bottom of the north.

A second bout of wintry weather is set to sweep up New Zealand in the coming 48 hours, with powerful 120km/h gales and heavy rain for the south.

Forecasters are warning Southland residents to prepare for surface flooding, slips and difficult and dangerous conditions as rain and snow lash the bottom of the country.

MetService has issued a heavy rain warning for the headwaters of the Canterbury lakes and rivers from 9am tomorrow.

The forecaster has told residents to expect up to 160mm of rain.

A warning is also in place for the ranges of the Westland District.

Further north, a strong wind watch is in force for Wellington, Wairarapa and the Marlborough Sounds.

The wind is due to hit the bottom of the North Island overnight Thursday, with severe gales in exposed places.

Potentially damaging gusts of 120km/h are expected to blast the Canterbury High Country from 9am tomorrow.

MetService has also placed a heavy rain watch on Fiordland north of Doubtful Sound from 10pm today.

Addtionally, there is a rain watch on the ranges of Buller and Grey Districts from 3pm and the headwaters of the Otago lakes and rivers from 3am.

MetService meteorologist Mmathapelo Makgabutlane said the rain and wind are due large weather system moving over the country.

While only the South Island is in the firing line tomorrow, the system is expected to creep up the country on Friday.

On Friday, MetService is expecting the front to move over the North Island while still hitting the South Island with snow at low levels.

“In addition to rainfall, strong winds will sweep across the country, affecting the South Island and lower North Island.

“Snowfall makes a return, mainly for inland parts of the South Island, which may impact road travel on high-level roads and mountain passes,” Makgabutlane said.

“This will also have a flow-on effect on temperatures as they take a dip, especially over the South Island. In a nutshell, almost all of Aotearoa will see something from this weather system.”

While that snow isn’t likely to warrant weather warnings, MetService said the bitterly cold conditions could stress livestock and affect local roads.

There is also a “moderate confidence” that winds may turn to severe gales on Friday morning in the Marlborough Sounds, Wellington and Wairarapa.

It comes after a wild start to the week where meteorologists counted around 7000 lightning strikes within the space of a few hours on Sunday afternoon.

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