Police are warning drivers to adapt to icy roads this morning and tonight as winter bites.
Yesterday there were sleet and snow flurries in Christchurch and heavier snow about Banks Peninsula and on the top of the Port Hills.
Snow in the South Island forced flights to be cancelled in and out of Queenstown, closed roads and schools in Otago and left about 260 households without power.
MetService meteorologist Stephen Glassey said parts of the South Island received a chilly start this morning, with lows of about -6 degrees Celsius at Mt Cook and at Pukaki, near Twizel, and -5.3C in Queenstown.
The lowest overnight temperature was -7, recorded at Molesworth Station.
Christchurch dropped to a low of -4C, which Metservice described as feeling "like -5C", while Ashburton went to -2.5C.
Temperatures would remain low during the day, Glassey said, with highs of about 10C across Canterbury.
"It's going to be a fine day. There could be just a little bit of high cloud later in the day," he said.
Police warned drivers to keep a close eye on icy road conditions throughout Canterbury.
Police and the Fire Service reported no weather-related call-outs overnight.
A car crashed into a house in Ashburton this morning, but it was not known whether icy roads or other factors were involved.
Southern police communications centre spokesman Rick Jury said the crash happened at the intersection of Pages and Saunders roads about 6.30am, but no one was injured.
Emergency services were also called to Rolleston after a cyclist slipped on ice on Byron St about 8am.
"A cyclist had just ridden into the back of a four-wheel-drive. His injuries are very minor," a police spokesman said.
Senior Sergeant Phil Newton, of Canterbury Highway Patrol, said heavy frosts would make many roads across the district treacherous.
"[That] will dramatically increase the risks of drivers having a crash - especially if they have a lapse in concentration," he said. "Our most important message to all drivers is to slow down whenever the weather turns bad."
Newton recommended that drivers increase following distances, clear ice and condensation from their windscreens and check the tyres, brakes, lights and windscreen wipers on their vehicles.
State Highway 87 from Outram to Middlemarch was closed this morning because of snow, while care was urged on most highways in the Otago region and drivers on all mountain passes were advised to carry chains.
Metservice issued a road snowfall warning today, saying snow showers were expected from late morning before turning to rain this afternoon.
Arthur's Pass and Haast Pass both reopened yesterday after slips closed them last week.
A "massive slip" about one kilometre west of the Otira township closed Arthur's Pass on Friday.
NZ Transport Agency senior network manager Mark Pinner said the road was expected to remain open overnight.
Single-lane access was opened about midday yesterday. Traffic through the area was being controlled and limited to 30kmh.
National Institute of Water and Atmospheric Research data shows the coldest temperature recorded in Christchurch during May last year was -2.8C, recorded near the airport on May 30.
- The Press
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