The snow gods giveth and the snow gods taketh away. New Zealand’s stellar snowfall start to the season hits a road bump this week while Australia’s snow drought gets broken. Meteorologist Alex Zadnik reports with his weekly snow forecast for SnowsBest.com.
Snow is the talk of the town this week and rightly so. The weather charts have taken a turn for the better in this regard, with a brutal slingshot of cold polar air set to sweep over Victoria and New South Wales during Friday and the weekend.
Another major feature of this impending weather system is the wind. Average wind speeds will be near 100km/h for alpine areas through Thursday night and Friday, with gusts to near 150km/h creating blizzard conditions. This means extremely poor visibility and the risk of downed trees on alpine roads, particularly those leading to Victorian resorts.
Ahead of the main blizzard, we will see a frontal system bring a few snow showers to the resorts through Wednesday and early Thursday. However the main event is from Friday through to Sunday. A developing low pressure system will send a surge of cold air across Victoria and NSW through this period as it stalls to the east of Tasmania.
Supporting this surge of cold Southern Ocean air will be a strong ridge of high pressure to the south of Tasmania. Impressively, this ridge of high pressure will extend south to almost polar latitudes, setting up a conveyor belt of very cold air across the Australian resorts. Snowfalls are likely below 1000m in Victoria and NSW on Saturday night and Sunday as the coldest part of the airmass sweeps through.
The heaviest snow falls for the majority of the Alpine resorts look like occurring through Friday and Saturday, with accumulated totals in the 30-50cm range. The highest runs at Hotham, Falls, Thredbo and Perisher should crack the half metre mark. Baw Baw (on the protected southern side of the range) may miss out at first but then cop similar totals from Saturday night into Sunday as winds shift towards the south.
Storm-force winds of over 100km/h can be expected through Thursday night and Friday, so conditions on the roads and in the mountains will be treacherous when combined with the falling snow. The distribution of our new snow base will also be influenced by these extreme winds, with large drifts in some areas and scoured thin cover in others.
Blizzard conditions will continue into Saturday but should begin to back-off a notch for most resorts during Sunday. This may open up a window for the keen and hardy to make their first tracks of the season. However, early to mid next week is the safest bet for more pleasant weather conditions in the mountains as a high pressure system moves in from the west. Snow quality will however be at its driest and best on Sunday and Monday due to the coldness of the airmass.
A deep low pressure system has brought heavy rain and gale-force winds to the North Island over the past two days. Whakapapa lifts were closed on Tuesday due to the gales.
This low will slip southwards during Wednesday and Thursday, helping weather conditions to ease on the North Island. Eastern parts of the South Island, north from around Dunedin, will see showers during Wednesday. Mt Hutt will see a mix of rain and snow, with the freezing level near 1800m.
The Queenstown and Wanaka ski areas will remain mostly dry on Wednesday and Thursday before the arrival of a weakening front from the west. This front looks like bringing more rain than snow to southern parts of the South Island through Friday with the freezing level near 2000 metres above sea level.
The snow level may lower enough on Saturday for the Remarkables, Treble Cone and Cardrona to pick up a few centimetres but there is the risk of rain on the lower slopes and at Coronet Peak. Rain showers may also increase for Whakapapa on the weekend with a relatively mild and humid northwest airflow developing ahead of a large low pressure system centred on the Australian side of the Tasman.
Colder air should edge its way northwards across New Zealand during Sunday and Monday, which could trigger some heavier snow falls for Whakapapa into next week, although perhaps only about the higher slopes. This cold air will be directed across the nation by a strengthening ridge of high pressure, so moisture levels (and in turn snowfalls) will be limited for the Queenstown and Wanaka resorts into the start of next week.
All in all there isn’t too much to get excited about in terms of natural snowfall over the next seven days.
Check back in weekly for Alex Zadnik’s snow forecast for the week ahead