How cold is too cold? Temperature is minus 43.6 Celsius in Sweden, a record

In January 1999, a temperature of minus 49 degrees Celsius (minus 56.2 Fahrenheit) was recorded in Sweden, which then tied the record set in 1951.

Sweden on Wednesday recorded its coldest January night in 25 years, with a reading of minus 43.6 degrees Celsius in the far north as a cold snap hit the country and neighbouring Finland.

Snow and frost cover the village of Vittangi in Kiruna municipality in the north of Sweden. (AFP)

"To put that into perspective, that is the lowest January temperature in Sweden since 1999," Mattias Lind, meteorologist at Sweden's national weather agency SMHI, told AFP.

In January 1999, a temperature of minus 49 degrees Celsius (minus 56.2 Fahrenheit) was recorded in Sweden, which then tied the record set in 1951.

Lind said that Wednesday's measurement was made at the Kvikkjokk-Arrenjarka station in Sweden's far north.

"It is the lowest temperature that has been recorded in this specific spot since measurements began" at the site in 1888, he said.

Several other stations recorded temperatures of below minus 40C in Sweden's northern parts.

While the region is used to seeing freezing temperatures, the recent cold snap has forced local bus operators to cancel services, and train operator Vy said Tuesday that it had cancelled all trains north of the city of Umea for several days.

Trains were also disrupted in neighbouring Finland, were a seasonal record of minus 38.7 Celsius was recorded Tuesday evening in the northern Lapland region.

Several instances of frozen water pipes were also reported, and Finnish broadcaster YLE said around 300 people in the city of Tampere were left without running water on Tuesday.

The cold front is expected to move south over the next few days, with residents of the Finnish capital Helsinki already seeing temperatures rise to minus 15C on Wednesday.