In the mountains there is currently a high risk of avalanches and in the lowlands it rains at very mild temperatures. In Liestal BL, 17.1 degrees were measured on Thursday and 16.2 degrees in Robbia in Ticino – the weather seems to be crazy on New Year’s Eve. According to Meteonews, the high will also determine the weather on Friday and New Years and will ensure plenty of sun in the flatlands.
But where do these mild temperatures in the middle of winter come from? The reason is the jet stream – the fastest air movement that blows on earth. On Wednesday, the jet stream blew warm air straight towards the Alps – at a speed of up to 300 km / h. The humidity then discharged as rain.
Air masses from the Caribbean
The warm air masses came partly from the Caribbean. “A few days ago they were still off the coast of Mexico,” says Meteoschweiz’s weather blog. Climatologist Stephan Bader told the “Tages Anzeiger”: “According to the current status, the warm phase does not seem to be particularly unusual.”
He assumes that the average daily temperature between December 20 and 31 is 4 degrees. This value is higher than in the past five years. In general, the temperature development in the last ten years is clearly pointing upwards.
However, there have always been fluctuations, as statistics from the past 50 years show. Nevertheless, according to Bader, the high temperatures are due not only to the jet stream but also to the general warming of the earth’s surface. (gin)