The month of December was one of the mildest in a century in the Nordic countries, according to meteorologists, with temperatures exceeding their normal seasonal average by four to five degrees Celsius in Norway and Finland.
This year began in a similar vein: pavements in all the Scandinavian capitals were uncharacteristically free of ice and snow, with the white stuff appearing only briefly in Oslo and Stockholm in early December.
Swedish daily Dagens Nyheter said several types of migratory birds have yet to leave for warmer climes, and showed cherry blossoms that normally only appear in the spring.
"In the north, winter has arrived, but in the south it's autumn according to the meteorological definition," the Swedish Meteorological and Hydrological Institute (SMHI) said.
Next door in Norway, local newspapers have collected reader photos of crocuses, daisies and dandelions, and budding branches of honeysuckle, while central Stockholmers have flocked to Kungsträdgården to snap up shots of the cherry blossoms in bloom.
The mild weather is caused by the same low-pressure area that has plunged large parts of the US and Canada into an unprecedented freeze.
"The link between the cold in North America and the mild temperatures here can be traced to a low pressure area that gave North America cold winds from the north, but which sent warmer winds from the southwest this way," said Reidun Gangstoe, a researcher at the Norwegian Meteorological Institute.
However, meteorologists predict temperatures will be closer to their seasonal average by the end of the week, when colder air is set to come in from Russia.