A cold front on Friday is expected to bring snow and freezing conditions to Canterbury.

Snow could fall to low levels in Canterbury this weekend.

Weather forecasting company, Blue Skies, said a cold snap on Friday night could bring snow to sea level and see up to 50 centimetres fall in high country.

"For a number of days now we have seen consistent forecast data suggesting this weekend will bring a very cold, snowy spell to Canterbury," the forecast said.

"Starting on Friday night or early Saturday, and extending through Sunday, quite likely into next Monday as well, periods of snow and sleet are expected over the region. Snow could fall as low as sea level, but we need to get a little closer to the start of the event to firm up on expectations. Above about 300 [metres] there is the potential for accumulations of 50cm or more."

MetService meteorologist Emma Blades said it was too early to tell if the southwesterly change expected on Saturday would bring snow to Christchurch. She said the forecast would be clearer from Tuesday.

"There is a southerly change on the horizon at the weekend.

"Temperatures will slowly decrease during the week ... At the moment there is a bit of uncertainty about the weekend.

"There is a chance of snow showers coming through at the weekend."