Rain, cold winds, snow reminder winter is coming - some warming on horizon

Monday, 23 May 2016

MetService National Forecast for Tuesday 24th May

Flooding is hampering travel on highways in Otago and Southland and dire weather conditions delayed attempts to rescue people trapped in their four-wheel-drive vehicles near Roxburgh.

Rescuers have now reached the 36 people in 13 vehicles who were trapped by snow on an off-road track.

Close to 1m of fresh snowfall on the road to The Remarkables ski area this morning.

Heavy downpours hammered Canterbury overnight and temperatures dropped to near-freezing as Wellington shivered through winter's first attack of the year.

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Significant surface flooding caused problems in parts of Christchurch, while MetService was forecasting snow down to 600 metres in the Canterbury High Country on Monday night.

The NZ Transport Agency has warned drivers of flooding on State Highway 90 at the Pomahaka Bridge, Otago, SH 97 between Mossburn and Five Rivers, Southland, and on SH 6 between Nokomai and Fairlight, Southland.

Surface flooding remains on roads around Dunedin

Caution was needed because of surface water on SH 8 between Raies Junction and Alexandra, and there were reports of snow and ice on SH 8 from Omarama to Cromwell. Snow flurries had been reported on Arthur's, Porters and Lindis Passes.

Winter driving conditions existed over the South Island, NZTA said. 'Watch for ice and grit particularly in shaded areas and on bridge decks. Carry chains when travelling the alpine passes.'

Leaves blocking mud tank grates in Dunedin.

South Canterbury ski fields have welcomed the cold snap. Roundhill Ski Area manager Simon Murrell said about 35 cm of snow fell near the top of the mountain overnight on Sunday. Mt Dobson Ski Area manager Bruce Foote said about 20cm of snow fell on the mountain over the weekend.

Southland District Council warned drivers of the need for caution. 'Care needs to be taken while driving on Southland roads today as there is widespread flooding,' the council said. Trees were also down in some places.

Flooding at the Ardlussa Bridge on the Mataura River near Balfour.

Wintry conditions are due to continue on Monday for most of the country, and the rest of the week is expected to be unsettled although some warming is on the way.

About 6.30am Queenstown Lakes District Council reported the Crown Range Rd, which was closed overnight trapping some vehicles, had reopened and was heavily gritted. Chains had to be carried as more snow was forecast. Wet and windy conditions were expected in the area.

Surface flooding remains on roads around Dunedin, with leaves blocking mud tank grates exacerbating the problem, Dunedin City Council maintenance engineer Peter Standring said.

Residents were urged to clear leaves and debris from grates to help drain water.

Surface flooding around Christchurch after overnight rain. Brougham Street at Opawa Road.

Dunedin's Musselburgh Pumping Station recorded 44.2mm of rain in the 24 hours to Monday at 11am.

The council had received several reports of garden and garage flooding.

Snow has trapped travellers and vehicles in parts of the South Island as months of unusually warm weather finally give way to a foretaste of winter.

We asked our NZStuff snapchat friends how cold it was where they were.

MetService said snow showers were expected on the Porters Pass road through Monday and on the Lindis Pass road during the morning. Overnight, light snow was reported on State Highway 2 over the Rimutaka Range north of Wellington but there is no snow warning for the road on Monday.

Cold snap brings end of Indian summer in Blenheim

A snowy cold snap has brought an abrupt end to Marlborough's Indian summer.

Heavy rain was recorded in the region last Wednesday, Friday and Sunday, and temperatures dipped over the weekend and on Monday morning.

A coating of snow was seen on the hills above the Waihopai Valley on Monday morning.

Plant and food scientist Rob Agnew described the weather as 'a bit of a sudden shock'.

Marlborough was still on track for the warmest May on record, but with a huge contrast between the first part of May and the last 10 days, Agnew said.

Usually there were five or six ground frosts in May, but the first ground frost of the month was seen on Sunday with a grass temperature of minus 1.2 degrees Celsius.

Snow on the hills around Palmerston North on Monday morning.

Near-freezing night for Wellington

On a night the Rimutaka Hill between Wellington and Wairarapa got a dusting of snow, the temperature in Wainuiomata dropped to 2 degrees Celsius early on Sunday, while Lower Hutt dropped to 3C and Wellington to 5C, MetService forecaster Karl Loots said.

Rain in recent days has helped ease dry conditions across much of the country but Niwa data shows soils in much of the North Island and the east of the South Island remain much drier than usual.

Loots said cold weather was expected to stick around on Monday but a warming trend was expected to arrive during the day, particularly in the North Island.

'It's going to be warmer for most places but we are expecting another band of rain coming over the country from tomorrow,' Loots said.

'Right now we're dominated, particularly the lower part of the country, by a could southerly to southeast flow,' he said.

'In the middle of tomorrow the flow, particularly over the North Island, goes northwest bringing in more tropical air.'

HOLY SNOWBALLS! It's been DUMPING so hard overnight & this morning that we've had to get our Snowcats to clear our mountain road

— Cardrona Ski Resort (@CardronaNZ) May 22, 2016

Hazardous driving conditions in Canterbury

Surface flooding could make driving hazardous on some Canterbury roads after heavy downpours hammered the region overnight.

Snow is also expected to fall down to 600 metres as a fresh southerly moves its way up the country, bringing more rain and hail for Christchurch on Monday.

About 24mm of rain fell in Christchurch in the 12 hours to 6am Monday, while 30mm was dumped on Banks Peninsula. Inland areas were sheltered from the rain, with Methven seeing just 1mm of rainfall.

Mount Cook this morning. https://t.co/WWUPv3iNj8 ^CL pic.twitter.com/Jw0dK0ykfL

— MetService (@MetService) May 22, 2016

The week ahead

Wet weather is expected to continue in Auckland on Monday, with MetService forecasting showers, a chance of thunder and hail, and strong westerlies. Top temperature is expected to be 16 degrees Celsius.

Wellington could stay dry until evening, with a 13C high and the arrival of northerlies, while more outbreaks of rain are likely in Christchurch, where the temperature is only expected to squeak into double figures.

Hamilton will have a showery Monday with a chance of thunder and hail and a 14C high, but Tauranga could have sunny spells and a 15C high.

New Plymouth could have some heavy and thundery showers, with a 16C high, while Napier bucks the trend of the rest of the country with sunshine and 18C.

ICYMI: Over 60,000 lightning discharges in NZ region this week. See https://t.co/tHLgKJ8s5o for daily maps ^CF pic.twitter.com/n23Q6PV31B

— MetService (@MetService) May 22, 2016

Palmerston North could have occasional showers and 14C, while Nelson is headed for 13C but the rain should stay away until evening.

Rain, possibly heavy, is expected to continue in Dunedin with a 10C high, while rain is forecast to ease in Invercargill during the afternoon and the temperature is due to reach 11C. Queenstown is headed for a 9C high and rain should ease in the afternoon.

In Timaru, wintery weather was set to ease on Monday, although Metservice was forecasting a further 20cm to fall above 800 metres in northern Otago on Monday night.