August 2025 relatively warm, dry and sunny

Preliminary August summary from GeoSphere Austria: Compared to the recent past, temperature +0.5 °C, precipitation -26 per cent, hours of sunshine +8 per cent.

Last August brought some cool and some hot weather conditions, with the overall balance of the Austria-wide evaluation showing above-average warmth.

‘In the preliminary monthly summary, August 2025 was 0.5 degrees above the average for the 1991 to 2020 climate period in the lowlands of Austria and 0.8 degrees above average in the mountains,’ says climatologist Alexander Orlik from GeoSphere Austria. ‘This puts August 2025 in 20^th place in the list of the warmest Augusts in Austria's 259-year measurement history in the lowlands and in 18th place in the 175-year mountain measurement series.’

Compared to the 1961-1990 climate period, which was not yet so strongly influenced by global warming, August 2025 was 2.4 degrees above average in the lowlands and 2.6 degrees above average in the mountains.

The number of summer days (at least 25 degrees) and hot days (at least 30 degrees) in August 2025 was above the long-term average at all altitudes.

Below 500 metres, there were eight hot days on average across Austria in August 2025. This corresponds to a deviation of 38 per cent from the 1991-2020 average. At altitudes between 500 and 1,000 metres above sea level, there were an average of five hot days, an increase of 85 per cent.

The number of summer days below 500 metres above sea level was just above the long-term average (+5 per cent), with an average of 20 summer days. There were significantly more summer days than the long-term average at altitudes of 500 to 1,000 metres above sea level, with 15 summer days (+15 per cent), and at altitudes of 1,000 to 1,500 metres above sea level, with 9 summer days (+45 per cent).

In the Austria-wide evaluation, August 2025 brought 26 per cent less precipitation than an average August. This made it one of the 30 driest August months in recorded history and similarly dry to August 2019 (-25 per cent) and 2024 (-28 per cent).

The regional analysis shows isolated above-average rainfall, such as in parts of northern Burgenland and western Vorarlberg.

The number of hours of sunshine in August 2025 was above the long-term average in most of Austria. The Austria-wide evaluation shows 8 per cent more hours of sunshine than in an average August.

In spring, leaf budding and flowering offer many opportunities for phenological observation. In summer, there is comparatively little going on. One of the few phenological phases that fall in August is the beginning of black elderberry fruit ripening.

This year, the average date of black elderberry ripening across Austria was 5 August 2025, which is 5 days earlier than the long-term average for the recent past (1991-2020) and ranks 11^th in the observation series since 1926. Compared to the long-term average for 1961-1990, the onset of black elderberry ripening was around 21 days earlier.

Translated with DeepL.com (free version)