WeatherBlog 20 2023/24 | April summer & short onset of winter

Current situation and outlook

The summery, hot and desert-dusty south-westerly flow was interrupted by a small drop of cold air, which brought temperatures back to a relatively normal level. However, this cooler interlude will not last long - the high pressure bridge between the European Atlantic coast and Eastern Europe is closing, the drop of cold air is being pushed away towards North Africa and the sun will be back tomorrow. 

The amount of fresh snow brought by the small and short-lived cold air drop is quite interesting. Today (Wednesday, 10 April) morning, stations on the main Tyrolean ridge are showing around 25-30cm of fresh snow and there should be some more during the day. The Geosphere issued a "snow warning" yesterday and the PowderGuide snow fall map is also surprisingly colourful today considering the temperatures of the last few days.

Saharan dust has also been on our minds a lot recently. Statistically, this is not very unusual, but perhaps the opposite effect is taking place here as with the temperatures: we are not used to the dust, so we notice it. The above-average temperatures have - it feels like - become normal, so we don't find a few warmer days so special. A recently published study on the frequency of Saharan dust events found that dust was actually transported to Western Europe (the study area mainly includes Spain and France) particularly often in 2020-2022. The dust transport is related both to quite small-scale processes in the desert areas and to the larger-scale weather situation. Dust must be present, it must be whirled upwards and then the flow in the higher atmospheric layers must bring the dust to us. The study explains which high and low pressure constellations are suitable for this and have caused the accumulation in the years 2020-22. There is no clear link to climate change, as the time series is not long enough and the development of the weather patterns is too ambiguous. A brief summary can be found here. The DWD has a few illustrative graphics on the topic, which show above all how unclear possible trends can be.