Warm front brings black ice in the east
The weather of the last few days is worth a little look back. On the one hand, there was long-awaited snow in the northern Alps - the latest ConditionsReports have a lot to say about the powder fun and the sometimes very tense avalanche situation (see e.g. overview of the weekend at LWD Tirol and SLF) as well as the still often inadequate base. On the other hand, there was all kinds of winter chaos, first in parts of Germany and then in eastern Austria, including school closures and paralyzed airports(e.g. Vienna Schwechat on Tuesday morning). Snow alone can sometimes pose a challenge, but bringing medium-sized airports to a standstill usually requires a few other ingredients.
For Vienna, these ingredients were already in place last weekend. After the passage of a cold front on Saturday, there was another surge of very cold air from the north and a largely clear night. The best conditions for strong cooling of the ground and the air layers close to the ground. With calm, cold high-pressure weather on Sunday with correspondingly stable stratification and another mostly clear night, the cold air on the ground continued to hold up well.
On Monday, warmer air masses arrived in higher layers, but the cold air on the ground remained unaffected. A warm front moved through on Tuesday night. Thanks to the actually mild air mass, the precipitation fell as rain and immediately froze on impact due to the very low temperatures on and just above the ground. The result: a considerable layer of ice on roads, airplanes, runways, etc. Further west, for example in Innsbruck, it has also become significantly warmer and somewhat more slippery, but without the freezing rain from the warm front, there was no such pronounced black ice problem.
It's a bit older and not from Vienna or Innsbruck, but we're taking this opportunity to point out this great video once again!
