Cantabrians are being warned to stock up on emergency supplies before a wintry blast brings heavy snowfalls tomorrow.
The Canterbury Civil Defence Emergency Management Group said large snowfalls could result in widespread road closures and power outages.
"People need to be prepared now for the possibility that this winter could again bring hazardous weather conditions to Canterbury,'' said Neville Reilly, Regional Civil Defence Group Controller.
"Everyone should have the necessities in place to be able to be self-sufficient for three days or more in the event of road closures and power cuts.
"This includes having stocks of food, water, warm clothing, fuel, alternative lighting and other emergency supplies on hand.
"We would also encourage people to make sure their homes are properly insulated.
Installing heat tape on exterior pipes can help prevent water systems from freezing,'' he said.
Neville Reilly said checking supplies in your car was also advised, and those considering driving over mountain passes were urged to take chains in case of snow, and to check road conditions and the weather forecast before setting out.
"Even in small quantities, snow can be hazardous. It only takes a few centimetres on a road to make driving dangerous.''
WeatherWatch said the polar blast would make Tuesday the coldest day of the year so far, bringing temperatures as low as minus 9C for isolated parts of the South Island.
Head analyst Philip Duncan said the cold change would be brutal, but shortlived.
"In fact as early as Tuesday afternoon the air flow over Southland and Otago will actually change and warm up - it may not be hugely noticeable but the coldest air in this polar blast will be over the North Island then pushing out east of New Zealand by late Tuesday,'' Mr Duncan said.
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