The national average June temperature in 2023 rose to 14.9 °C. This is 2.3 °C above the 1991-2020 norm. This means that Switzerland can look back on the fifth warmest June since measurements began in 1864. The five warmest June months were all recorded after 2000. The previous June record of 17.3 °C dates back to the hot summer of 2003. June in Switzerland has become 2.5 °C warmer from the pre-industrial period 1871-1900 to today (1993-2022).
Line graph of June temperature in Switzerland.
Fig. 1: The June temperature in Switzerland since measurements began in 1864. The current June (red dot) reached 14.9 °C or 2.3 °C above the 1991–2020 norm (green line). The red line shows the 20-year moving average.
Persistently dry and sunny in the north thanks to the bise
In the first 15 days of the month, Switzerland was on the southern edge of a high-pressure area that persisted between the North Atlantic, the British Isles and the Baltic. As a result, the bise (a dry east to northeast wind) dominated the weather on the northern side of the Alps. At the Zurich-Kloten measuring station, June brought over 180 hours of bise (as of June 29, 2023). This is by far the highest June value in the available automatic measurement period since 1981. The number of hours of bise in June varies greatly from year to year. Due to the short study period and the strong fluctuations, no reliable trend for the hours of bise in Zurich-Kloten can be determined so far.
Bar graph of annual breeze hours in June
Fig. 2: Hours of gusts in June at the Zurich-Kloten measuring station since automatic measurements began in 1981 (as of June 29, 2023, morning). Hour of gusts: Average wind direction between 10 and 100 degrees, average wind speed 10 km/h or more. The gray line shows the 10-year moving average.
The bise brought a lot of sun, often pleasant summer temperatures with light to moderate winds and little rain. At some measuring locations, no rain fell at all in the first half of the month. In Güttingen on Lake Constance, Buchs-Aarau and Wynau in the central midlands, there was no precipitation until June 18. Less than 1 mm of rain fell in St. Gallen, Zurich and Bern during this period.
sunshine record
The persistent high pressure weather in the first half of the month led to a high monthly sunshine duration, especially north of the Alps. In northern Switzerland, it was one of the sunniest June months since measurements russia phone number library began. The Basel-Binningen measuring station reported over 320 hours of sunshine. All previous June highs since measurements began in 1886 were below 300 hours of sunshine. June 2023 was the third sunniest month in the Basel measurement series. Only July 1905 with 338 and July 2022 with 351 hours of sunshine brought more sunshine. Lucerne also recorded the sunniest June since measurements began in 1901 with over 290 hours of sunshine. In Lucerne, it could also be the sunniest month in the measurement series.
Bar graph of the hours of sunshin
Fig. 3: The June sunshine duration in hours since measurements build a successful email campaign strategy began in 1886 at the Basel-Binningen measuring station (as of June 29, 2023, morning). The gray line shows the 20-year moving average.
thunderstorms in the south
South of the Alps, the air was moist and unstable in the first half of the month, caused by a low-pressure area over the Gulf of Genoa. Thunderstorms with showers occurred almost daily. In Stabio, a heavy thunderstorm on agb directory June 11th brought 63.3 mm of rain within two hours. A two-hour total of this amount is reached or exceeded in Stabio approximately every three to eight years. On June 12th, Lugano recorded a ten-minute total of 22.0 mm. A value of this amount is also reached or exceeded in Lugano approximately every three to eight years.