Police have issued a plea for Southern motorists to take extra care on icy roads following a rash of crashes this morning, and flights have been disrupted at Dunedin Airport.
"We have attended over 25 crashes across the district in the past 4 hours due to ice and black ice on roads in South Otago, Gore and Invercargill," District Road Policing Manager Inspector Tania Baron said about 10am.
Police encouraged drivers to be aware of areas with black ice and to watch following distances and speed.
Ice is delaying and cancelling planes at Dunedin Airport this morning.
No planes are landing or taking off at the airport.
Dunedin Airport spokeswoman Megan Crawford said there was ice on the runway and it was raining.
"It was 0degC an hour ago and it's still raining. We need a little bit more heat on the runway before we can get things moving again.''
Flights to and from Christchurch, Wellington and Auckland had been affected.
Full details are available on the airport's website
Air New Zealand's NZ5057 from Christchurch and NZ5443 from Wellington were cancelled.
Air New Zealand flights NZ50162 to Christchurch and NZ5048 bound for Wellington were cancelled.
NZ410 to Wellington and Auckland, due to depart at 6.25am, and NZ5012 to Christchurch, due to depart at 7.30am, have been delayed. Crawford said roads were also affected by ice.
"It's pretty bad. There's a police cordon turning people back at the turn-off to the airport [on State Highway 1]. Unless they really need to go south they're turning them back."
The New Zealand Transport Agency reported State Highway 1 between Milton and Allanton, State Highway 87 between Outram and Kyeburn and State Highway 85 between Kyeburn and Palmerston were affected by ice.
Police urged special caution on the State Highway from Allanton through to Waihola, as there had been several crashes on that stretch of road this morning.
Queenstown Lakes District Council reported icy patches and grit on dry roads this morning, with temperatures ranging from -3degC to 1degC across the district.
Motorists in the district were advised to watch for slippery areas on the Crown Range, Cardrona Valley Rd, Kawarau Gorge, Fernhill, Queenstown Hill, the Glenorchy road around Wilson Bay and Bob Cove, and also in and around Wanaka township. All had been gritted.
The Clutha District Council is reporting black ice throughout the district, and contractors have several trucks gritting the roads.
"Road users need to be aware that it is not just the sealed roads that are slippery. Due to this morning's rain the gravel roads have turned into sheet ice in places, making some roads hazardous. Extreme care is required," a spokeswoman said.
Contractors in Central Otago reported hard frost conditions with areas of fog, and temperatures ranging between -3degC and -5degC.
Caution was advised particularly on bridge decks, hill sections and shaded areas.
Access to Dansey's Pass Rd is restricted to 4WD vehicles due to snow.
The Dunedin City Council reported only isolated areas of frost on roads in the area.
