Manager James McKenzie said the snowfall was a "big game changer for the season".
Only 30cm of natural snow had fallen so far this ski season before the snowstorm this week.
"This is like a gift from the gods," McKenzie said.
The ski area had planned to open today.
McKenzie said Friday, Saturday and Sunday will be Car Pool Priority Days as the ski area is expected to be busy.
The snow on Tuesday and Wednesday fell to about 300m above sea level across most of Canterbury, settling on the ground in Methven and around the foothills of the alps.