And as a growing number of European ski resorts at lower altitudes struggle to provide adequate snow cover for their early-season visitors, the WMO pointed to widely accepted peer-reviewed scientific data from the UN Intergovernmental Panel on Climate Change (IPCC) indicating that the frequency of cold spells and frost days “will decrease”.

“Strong declines in glaciers, permafrost, snow cover extent, and snow seasonal duration at high latitudes/altitudes are observed and will continue in a warming world,” the IPCC said.

According to the UN agency, New Year temperatures soared above 20 degrees Celsius (C) in many European countries, even in Central Europe.

National and many local temperature records for December and January were also broken in several countries, from southern Spain to eastern and northern parts of Europe, WMO said.

Temperatures lift off in Spain

At Spain’s Bilbao airport, a reading of 25.1C on 1 January smashed the previous all-time record established 12 months earlier, by 0.7C.

And in the eastern French city of Besançon, which is usually chilly at this time of year, temperatures hit a new all-time high of 18.6 degrees on New Year’s Day, 1.8C above the previous record, dating back to January 1918.

In the German city of Dresden, the 1961 New Year’s Eve record of 17.7C was left trailing by the 19.4C reading taken on 31 December 2022, just as Poland’s Warsaw residents saw in the new year with temperatures peaking at 18.9C, a staggering 5.1C higher than the previous all-time record for January, from 1993.

Further north, in Denmark’s Lolland island, 2023 started with a new high of 12.6C, overtaking the 12.4C record set in 2005.

Highs and lows

WMO attributed the warm spell in Europe to a high-pressure zone over the Mediterranean region which encountered an Atlantic low-pressure system.

Their interaction “induced a strong south-west flux that brought warm air from north-western Africa to middle latitudes”, the UN agency explained, adding that this hotter-than-normal air “was further warmed when passing the North Atlantic, due to a higher-than-normal sea surface temperature”.

Highlighting the influence of warmer sea waters on weather patterns, the WMO noted that in the eastern North Atlantic, sea surface temperature was 1C to 2C higher than normal, and “near the coasts of Iberia, even more”.

“All this caused record-breaking heat in several European countries on New Year's Eve and New Year's Day,” WMO concluded.

Sign of the times

The weather extremes experienced in Europe are projected to carry on increasing, the WMO warned, as it referenced recent analysis published with “high confidence” by the influential UN Intergovernmental Panel on Climate Change (IPCC). “Regardless of future levels of global warming, temperatures will rise in all European areas at a rate exceeding global mean temperature changes, similar to past observations,” the IPCC said.

According to the IPCC’s regional fact sheet for Europe, “the frequency and intensity of hot extremes, including marine heatwaves, have increased in recent decades and are projected to keep increasing regardless of the greenhouse gas emissions scenario”.

The panel’s experts further warned that “critical thresholds” for the environment and humans “are projected to be exceeded for global warming of 2C and higher”.