Snow blast could close highways in last gasp of winter

Monday, 21 October 2019

Spring snow on Porters Pass in Canterbury in early October meant slow travel for vehicles, but family fun for the Chapmans.

MetService warns six major highways could be closed by snow as freezing weather sweeps through south.

A deep low pressure system moving across the central South Island could likely mean snow down to 300 metres on Wednesday morning in the Kaikōura ranges, Canterbury, and Central Otago.

The late season snow dump could cause chaos on the roads, with as many as six likely to be closed or affected by snowfall: Lewis Pass, Arthur's Pass, Porters Pass, Lindis Pass, Crown Range Road, and Milford Road.

'Although it is not common to get snow this low at this time of year, we've seen it before during those cooler, more unsettled spring seasons,' meteorologist Kyle Lee said.

Snow is expected to fall to 400m in Central Otago on Tuesday evening and 300m further north to Kaikōura.

* Commerce Commission investigating Niwa and MetService

* Extreme weather linked to greater public trust in science, survey shows**

Temperatures in Wanaka and Alexandra should drop to zero degrees Celsius, with snow to 400m in Central Otago.

The rain and strong winds would move over the North Island from Wednesday. Snow is likely to affect the highest roads over the Central Plateau at about 800m to 900m.

Light winds on Friday should be followed by a developing northerly wind on Saturday, bringing warmer temperatures.

The blast would bring a significant drop in temperature in lower parts of the island, with lows of zero in Wairarapa, Masterton and Dannevirke.

Auckland would escape the front, with a low of 10C and a high of 14C, though it will be hit by rain and winds.

Wellington should expect similar conditions, though a little chiller at 6C overnight and a high of 12C.

Christchurch would see a low of 4C overnight, but will get some sun and a high of 12C in the afternoon.

A second front on Thursday would bring scattered rain to the South Island and keep temperatures low.

'Once that rain clears on Thursday, the forecast for Labour weekend will be mainly fine,' Lee said.

Light winds on Friday should be followed by a developing northerly wind on Saturday, bringing warmer temperatures.

'Temperatures will start jumping up to about 20 degrees, so people should notice a difference,' he said.