The Finnish Meteorological Institute (FMI) has issued a warning of hazardous driving conditions, especially in central and southern areas of the country, for Christmas Eve.
Snow showers are forecast for much of the country throughout the day, with snow blizzards also expected in some parts.
FMI meteorologist Sini Tenhunen advised motorists to give themselves plenty of time to complete their journeys over the holiday period, as roads are likely to be especially slippery on Christmas Eve and Christmas Day.
According to the national traffic management agency Fintraffic, Thursday 23 December will be the busiest day of the Christmas on Finnish roads and delays are expected on highways 4 and 9.
Police have also urged motorists to check the weather forecast and, if possible, adjust their departures accordingly.
Low pressure front
The FMI has forecast that the whole of Finland will wake up to a White Christmas on Friday morning.
A low pressure front moving over the country is expected to bring snowfall to many parts, with the depth of snow falling ranging from more than 30 centimetres in Finnish Lapland to no more than a few centimetres in the southwest.
"In other words, Santa Claus will be distributing gifts to children in white weather, even though it might be a thin layer," Tenhunen said, adding that temperatures across the country are expected to drop well below freezing throughout the day on Christmas Eve.
"It might be as low as 20 degrees below zero in the east and north," she said.
Strong winds will also add to the chill factor.
"It will be colder than usual [for Christmas Eve], but nothing out of the ordinary is expected either," FMI meteorologist Ville Siiskonen said.
The Finnish Meteorological Institute has been recording variations in the temperatures and snow conditions at Christmas since 1991, and the definition of a 'White Christmas' is that there is at least one centimetre of snow on the ground at 9am.
The data reveals that usually every second Christmas on the southern and western coasts of the country and in the southwestern archipelago is a White Christmas.
"When we go a little inland in the south, six to eight out of ten Christmases are white," Siiskonen said, adding that the further north, the better the chances.
"In the North, it is safe to say that almost every Christmas is white," he said.