Zach Crawford
2 minutes 32 seconds
The month of April begins with signs of winter in many European countries. The arrival of air masses of recent polar origin leads to temperatures well below typical averages for the late cold period but also to statistically significant snowfalls, as happened in Serbia and Bosnia. In Belgrade, 17 cm of snow on April 5 is the new record for snow accumulation for the month of April, 7 cm more than the previous record in 2021.
Late cold is not uncommon in early spring; The current month will be the third of April in a row, with cold winters and frosts spreading in Europe.
This unusually cold phase comes on the heels of the first months of 2023 being dominated by above-average temperatures in Europe. Sudden changes in the weather, from spring to the return of winter in a few days over central-western Europe, are not new between the end of March and the beginning of April; In the past we remember the years 1969, 1989, 2005, 2021 and 2022.
It is a long standing trend. The winters of the 2000s often had a strong anti-hurricane footprint in Europe, especially at the start of the season with a cyclone against Europe. The winter heating trend has an increase in anomalies +0.15°C/decade. Winter and spring are seasons that have seen an increase in heat over the years; Hot records are more frequent than cold ones. It becomes increasingly rare to break the cold record in warm climates, but it can happen. It can also happen that the temperature jumps from hot to cold quite suddenly, as in this case. It must be said that the seasons in general have changed in duration With medium ones they last less as the summer goes on. This has ramifications for nature
For example, the recent mild temperatures have fooled the vegetation which precedes flowering and therefore suffers more from late cold snaps. In fact, increasingly mild winters awaken vegetation earlier, which becomes more vulnerable to spring frosts. However, compared to previous years, there were some cold spells in January and February which slowed down the rapid germination process.
It must be said that these last few years have been marked by stratospheric warming, events that weaken the polar vortex causing important variations in the circulation. Strawarming is well known and is completely normal events and can cause significant traffic anomalies. According to a recent study “there is no strong evidence for future changes in major warming in the stratosphere” during the 21st century. “The weakening of the polar vortex has drained this cold lake towards Europe. This situation occurs with a difference considered as the maturation of the polar vortex as winter shifts forward characteristic of the different seasons of the past twenty years.
Laurence Malcom
