Warmer weather on way after polar blast

MetService says a reprieve from cold and windy weather isn't expected until midweek after a polar blast hit much of New Zealand today.

Heavy rain, blustery winds and snow have hit many parts of the country in the past couple of days, causing flooding and road closures.

MetService meteorologist Mmathapelo Makgabutlane said the cold, showery southwesterly flow would continue into Tuesday, with widespread frosts expected in the South Island. 

More settled and sunnier weather is forecast for Wednesday as a ridge of high pressure moves over, before the rain and wind returns for the South Island later in the week.

"To go from snow to sunshine back to blustery winds all in a matter of days? It's yo-yo weather at its finest," she says.

However, conditions will be warmer than many experienced today. Daytime highs around much of the South Island look to hit the mid-teens from midweek, whereas many places were in single digits for most of Monday.

MetService's seven-day forecast for Dunedin and parts of inland Otago show plenty of sun with some odd showers for the rest of the week.

The forecast comes amid falls of snow in Dunedin city and other parts of the region as a polar blast moves across much of the lower South Island.

This morning, MetService updated its road snowfall warnings for southern areas and authorities warned of dangerous driving conditions in Southland and Otago. 

Snow flurries have been making their way up the South Island and hit Dunedin, as expected, by about noon.

MetService issued a heavy snow watch for Central Otago south of Lake Wakatipu and Roxburgh, Clutha, Southland, Stewart Island, and Fiordland south of George Sound until 3am Tuesday.

Strong southwesterlies are expected to bring frequent showers and snow to low levels.

Heavy snow may fall above 300m at times in these areas, and may approach warning criteria in places. Residents have reported many thick and wet flurries across the region, but for the most part the snow has been settling only in higher areas.

Waka Kotahi NZTA has issued snow and ice warnings for all Southland State Highways (SH 1, 6, 93, 94, 95, 96, 97, 98, 99).

State Highway 1 from Dunedin to Waitati is also under a road snowfall warning until midnight. About 1cm of snow may accumulate above 100m at times.

The Crown Range Road was closed this morning but reopened at about noon. 

SH93 between Mataura and Clinton was also closed for about 2 hours from 7am but has now reopened.  

Gore District Council said in a Facebook post residents should be careful when driving around the district, as some areas were affected by snow.

While all local roads were currently open, there is 1- 2cm of slush on some of the higher altitude roads. These roads include; Crawford Road, Diamond Peak Road and Kaiwera Road.

Waka Kotahi NZTA has told drivers to take extra care on State Highway 87 between Kyeburn and Outram, and SH85 between Alexandra and Kyeburn due to snow and ice. 

Central Otago District Council also warned motorists to slow down and drive to the conditions as snow falls on roads throughout the Maniototo, Manuherika and Roxburgh areas. 

Temperatures are expected to drop as low as -2°C inland.

MetService's Mmathapelo Makgabutlane earlier said it was possible snow would fall and settle to about 300m in Dunedin’s hill suburbs, but it was unlikely to create traffic disruptions.

"There is a lot of cold air on the way that will bring snow to 300m-400m, and there could be some snow flurries even lower than that.

"It looks like it will be arriving in Dunedin anytime from late morning.

"At this point, it looks like the heaviest snow will happen a bit higher up, but if it does snow in Dunedin and it starts settling on the road, people should take extra care on the roads.

"It is definitely an evolving situation, so we’ll be keeping a close eye on it."

It would certainly be very cold, the mercury only reaching a high of 6°C, she said.

"It’ll feel pretty chilly and wintry. If there are some snowflakes floating around, it’ll feel like a proper winter’s day."

Further north, about 50 people were forced to spend the night in Arthur's Pass in Canterbury after snow shut State Highway 73 between Springfield and Castle Hill. 

Porters Pass reopened at about 12.30pm but winter driving conditions are still in place and road users are advised to take extra care.

SH7 Hanmer Springs to Springs Junction (Lewis Pass) has reopened.

In Central Otago, Hawksburn Rd, from Clyde to Cromwell is closed and Danseys Pass Rd is restricted to 4WD access only. 

john.lewis@odt.co.nz /additional reporting RNZ