The national average temperature from December to February was 0.7°C, the Federal Office of Meteorology and Climatology, MeteoSwiss, said on Friday.
Between 1864 and 1990, the average winter temperature was below 0°C. But in the past 30 years, mild winters have occurred at increasingly shorter intervals, according to MeteoSwiss. A winter with a national average temperature above 0°C has been observed only four times since 1864, when measurements were first recorded.
February was the second mildest on record, with a national average temperature of 1.6°C. The average February temperature between 1981 and 2010 was -2.3°C. In Biasca, canton Ticino, the mercury reached a high of 24.6°C on February 24, a new national record.
The warmer temperatures have affected flora. Spring flowering, for example, occurred earlier, with some species appearing 25 days earlier than average.
February also saw unusually turbulent weather. A few regions recorded as many as 23 days of storms. In the first half of the month, three winter storms hit Switzerland. The strongest, Storm Ciara (Sabine), brought wind gusts of 90 to 120 km per hour on the central plateau, and as much as 200km per hour on the Alpine ridges.
The mild winter continues a trend of warmer weather in Switzerland. The year 2019 was the fifth warmest on record; that same year the summer was the third warmest since 1864.