Dr Eddie Graham, a meteorologist at the University of the Highlands and Islands, has researched records to find the Northern Hemisphere has warmed by about half a degree centigrade in the past 40 years.
Citing research by Rutgers University in the US, Dr Graham said the total annual number of snow days per year over Europe has decreased, but with a large inter-annual variability. He added: "This overall decrease in snow cover, however, has not been replicated during the month of December - an anomaly that bucks the trend of decreasing snow cover in most other months.
"Indeed, it appears that December has even become slightly more snowy over the past 40 years across Scotland and Europe as a whole - we only need to recall the very snowy Decembers of 2009 and 2010 to confirm this."
Dr Graham predicts an increasing chance of colder weather by the time Santa arrives, with the odd sleet flurry.