On Switzerland’s national holiday, not all regions are blessed with good weather. An analysis of weather data from the last few decades shows that the evening celebrations on 1st August in the western part of central Switzerland were only rarely rained off. Rainy 1st August celebrations were mostly seen in the Alps.
Analysis of the automated measurements since 1982 shows significant regional variation. Mild temperatures and precipitation-free evenings on the Swiss national holiday on 1st August are not guaranteed.
The region around the nation’s capital city of Bern came out well on top for the analysed period from 1982 onwards, with only a handful of rainy evenings on 1st August. Favourable conditions were also found in Basel and Geneva, as well as in Lugano on the southern side of the Alps.
Rain was more frequent towards the east and in the Alps. In Adelboden and Glarus, for example, it rained in the evening of 1st August every other year on average.
The regional variations are mainly attributable to summer thunderstorm activity, which is more pronounced in the Alpine regions than in the lowlands.
Despite it generally being the warmest time of the year, 1st August can be fairly chilly, depending on the region. Depending on the weather conditions, the temperatures on the northern side of the Alps on the evening of the national holiday can be unpleasantly low, even in the lowlands, so a jumper or jacket may be called for. In Ticino, on the other hand, temperatures are generally very pleasant.