Thunderstorms for north, snow, avalanche threat leaves highway closed

Deep snow is cleared from alpine passes across the South Island. Photo / NZTA

Thunderstorms will continue to shake the north today as motorists travelling on South Island alpine roads are warned to carry chains after heavy snow caused major disruption.

The country is waking to a chilly, wet morning with temperatures in single digits south of Auckland.

Snow is continuing to fall across Central Otago this morning and road snowfall warnings remain in place for the Desert Rd, Porters Pass and Crown Range Rd. In some regions it is not expected to stop snowing until after lunch.

Minimum temps expected for tomorrow morning. Cold start in the east and high lying regions as showers gradually clear ^KL pic.twitter.com/6ERuh70QMw

— MetService (@MetService) September 10, 2017

Many South Island passes were closed by snow and ice, and slips have left one closed and another down to one lane after a bitter cold snap swept across the country at the weekend.

This morning Milford Sound remains cut off and the Lewis Pass is closed by a slip. Porters Pass is down to one lane after debris spilled across the road.

Road crews are now clearing the Lewis Pass blockage and authorities expect the road to be reopened by 8am.

Chains are essential travelling on the Lindis Pass and State Highway 6 from Kingston to Jacks Point.

The road is now expected to be cleared by 8am. ^JP https://t.co/RLMQVT2BA3

— Waka Kotahi NZTA Canterbury & West Coast (@WakaKotahiCWC) September 10, 2017

The NZ Transport Agency said after a weekend of heavy snow avalanches now posed a high risk on SH94.

The road was closed from Hollyford and was not expected to be reopened until this afternoon at the earliest. NZTA said a 7km track was cleared into the tunnel area yesterday but more heavy machinery would be needed to finish the job.

It was hoped to have the highway partially reopened late today but it would initially be restricted to essential traffic only.

Very icy over the Crown Range road with light snow falling. Chains must be carried. Loose grit across the district. Slow down & take care.

— QLDC (@QueenstownLakes) September 10, 2017

In the north snow showers are expected to fall until 1pm on the Desert Rd with up to 2cm of snow settling near the summit this morning. No other North Island roads are under a road snowfall warning.

My drive to work this https://t.co/E6RAsdCGvD was your commute? @TheCountry @PhilipDuncan @WeatherWatchNZ @NZStuff @nzherald @TheACCnz pic.twitter.com/TzFJwak0hK

— Andrew Thompson (@Pandasport) September 10, 2017

The upper half of the North Island remains under a threat of thunderstorms with MetService warning the unstable air mass is continuing to affect regions for a fifth successive day.

This morning lightning and thunder was expected to rumble across Taranaki to Northland with strong wind gusts and hail up to 15mm in diameter.

Tēnā koutou Aotearoa. It's a showery looking picture, with some thunderstorms affecting Te Ika a Māui today https://t.co/hnwmGxU1gR ^PL pic.twitter.com/93sLJ19HjM

— MetService (@MetService) September 10, 2017

After lunch the thunderstorm threat was greatest from Coromandel Peninsula and the north of Waikato northwards. The storms were expected to be accompanied by heavy rain and hail measuring up to 20mm in diameter.

Afternoon and evening showers were also expected over the northeast of the North Island with a moderate threat of thunderstorms for Bay of Plenty and north of Gisborne.

Today's temperatures

Auckland: Showers, some heavy and possibly thundery until evening. Strong southwesterlies. 14C
Tauranga: A few showers, clearing this evening. Westerlies.14C
Wellington:Cloudy, showers. Southerlies. 11C
Christchurch:Showers, becoming fine. Southwesterlies.13C
Dunedin:Showers, heavy during morning, becoming fine. Strong southwest winds.11C