With a deviation of 2.1 degrees Celsius in the lowlands above the average for the climate period 1991 to 2020, July has become the fourteenth above-average warm month in a row, while in the summit regions it was 2.0 degrees. “This puts second place in the lowlands in the series of the warmest July months in the 258-year history of measurements and fifth place in the mountains in the 174-year mountain measurement series,” summarized climatologist Alexander Orlik from Geosphere Austria. Compared to the climate period 1961 to 1990, which was not yet so severely affected by global warming, July 2024 was 3.8 degrees above average in the lowlands and 3.6 degrees above average in the mountains. The first ten in the series of warmest Julys in recorded history since 1767 are 2015, then tied 2006 and 2024, then 1983, then tied 2013 and 1994, then tied 2022, 2010 and 1995, then 2023.
The number of hot days with at least 30 degrees was also significantly above average in July 2024. In the state capitals, for example, there were (including the forecast for July 31) 17 hot days at the Vienna Inner City weather station this July (average for the period 1991 to 2020: eleven), in Eisenstadt 16 (average nine), St. Pölten twelve (average seven), Linz twelve (average six), Salzburg Freisaal eight (average six), Innsbruck University eleven (average eight), Bregenz five (average four), Graz University 14 (average six), Klagenfurt Airport 14 (average seven).
The nights had extremely high temperatures in some regions. For example, at the weather station in Vienna’s inner city, the average minimum temperature this July was 20.7 degrees. This is the highest value since measurements began in 1985. “At the weather station in Vienna’s Hohe Warte, the highest value since measurements began in 1872 was 18.9 degrees,” reported Orlik. New records for average minimum temperatures for July were also set in Mariazell in Styria, in Weyer in Upper Austria, in Litschau and Zwettl in Lower Austria, and in St. Jakob in the Tyrolean Defereggental.
Above-average number of tropical nights
There were also a few new records for July in terms of the number of tropical nights with a low of at least 20 degrees. Eisenstadt recorded 13 tropical nights this July (the old July record was ten in 2015), and the weather station in Vienna Hohe Warte also recorded 13 tropical nights (the old July record was eleven in 2015). The weather station in Vienna Innere Stadt recorded 19 tropical nights, exactly the same as the record in 2006. St. Pölten also recorded five tropical nights, the same as the record in July 2007.
In the Austria-wide evaluation, July 2024 brought 23 percent less precipitation than an average July. In the east in particular, it was extremely dry in places with a deviation of minus 50 to minus 95 percent. In many regions, however, the month brought a lot of rain in a short period of time with heavy thunderstorms.
At the Sonnblick Observatory, at around 3,100 meters above sea level, however, the last remnants of winter snow melted as early as July, similar to 2023 and 2022. “No snow on the Sonnblick summit is extremely unusual in July. Before 2022, the lowest snow depth in a July on the Sonnblick was 30 centimeters and the snow cover disappeared, if at all, only for a short time in late August or early September,” Orlik noted.
