The climate in Switzerland

Switzerland is a landlocked country in Central Europe with a varied climate influenced by the surrounding high Alps and the resulting diverse topography. The country is known for its mountainous regions, which account for more than 60% of the country's surface area.

The continental climate provides cold winters and warm summers. However, due to the mountainous topography, there can be significant variations in temperature and precipitation depending on altitude and location.

In the lower-lying areas, which include cities such as Zurich and Geneva, the climate is relatively mild, with average temperatures of about 10 °C in winter and 20 °C in summer. The region experiences frequent rainfall throughout the year and occasional snowfall during the winter months.

In the mountainous regions, the climate is much colder and snowier. The Swiss Alps have an alpine climate with long, snowy winters and short, cool summers. The higher elevations can experience freezing temperatures year-round, making these areas ideal for winter sports in particular.

Switzerland is also known for its microclimates, which can cause significant variations in temperature and precipitation over short distances. For example, Ticino in the south of the country has a Mediterranean climate with warm temperatures and frequent sunshine, while Engadin in the east has a cold, dry climate with little precipitation.

Temperature records of the last 75 years

The hottest temperature measured from 1949 to February 2024 was reported by the Geneva weather station. In July 2015, the record temperature of 39.7 °C was reported here. The hottest meteorological summer from June to August, based on all 8 weather stations in Switzerland below 810 meters altitude, was recorded in 2023 with an average temperature of 20.5 °C. This average temperature will normally be measured every four to six hours, thus also including the nights. Normally, this value is 18.5 degrees Celsius. The average maximum daily temperature at that time was 26.6 °C.

The coldest day in these 75 years was reported by the Basel Binningen weather station. Here the temperature dropped to -19.3 °C in February 2012. Basel Binningen lies at an altitude of 317 meters above sea level. The coldest winter (December to February) was in 1963 with an average temperature of 0.1 °C. In Switzerland, it is usual to have about 3.6 degrees more at 3.7 °C for this three-month period.

The most precipitation fell in November 2014. With 19.6 mm per day, the Lugano weather station recorded the highest monthly average of the last 75 years. Incidentally, the region with the most rainfall for the whole year is around Lugano. The driest region is near Sion.

Record months last year

We compared the record values of the past months with those of the same months in previous years. We used the same criteria to examine the respective maximum and minimum values in the categories of average temperature, precipitation, hours of sunshine and the maximum and minimum temperatures measured throughout the country. We have listed all measured values that have not been reached in Switzerland for 10 or more years.

• At 4.44°C, December 2023 was the warmest December in 21 years (4.67°C in 2002).
• With 5.71 liters of precipitation in 2023, November was the wettest in 21 years (8.35 l/m² in 2002).
• At 18.80°C, September 2023 was the warmest September in 62 years (19.03°C in 1961).
• The highest temperature of 31.70°C reached in September 2023 was last seen in the same month 12 years ago (32.30°C in 2011).
• With 10.07 hours of sunshine per day in June 2023, there was more sunshine than in any June in the last 20 years (10.17 hours in 2003).
• With 2.80 liters of precipitation in 2023, March was the wettest in 17 years (4.02 l/m² in 2006).

The most recent months after February 2024 are not yet available here. We only calculate climatic comparisons after a large number of weather stations on a continent have checked and published their data.

Long-term development of temperatures from 1950 - 2023

In contrast to single record values, long-term development cannot simply be brought about by all weather stations in the country. Both the number and the locations are constantly changing. An average value would give a distorted result. If several measuring stations in particularly cold mountain or coastal regions are added in one year, the average would decrease as a result of this alone. If a station fails during the summer or winter months, it does not provide any values and distorts the average again. The subsequent long-term development was therefore reduced to only 1 measuring points in order to have comparable data over as long a period as possible.

In the years 1950 to 2023, there were only these 1 weather stations in the whole country, which reported continuous temperature values (Zurich). From these weather reports, we have created a long-term development that shows the monthly average temperatures. The hottest month in this entire period was August 2003 at 22.7 °C. February 1956 was the coldest month with an average temperature of -8.7 °C.

The average annual temperature was about 9.1 °C in the years after 1950 and about 10.8 °C in the last years before 2023. So in less than 74 years, it has increased by about 1.7 °C. This trend only applies to the selected 1 weather stations in Switzerland. A considerably more comprehensive evaluation of global warming has been provided separately.

Data basis and methodology

The data from the individual measuring stations are based on the archives of the German Weather Service, individual values averaged and supplemented by own elements. In order to determine a representative national average, average values were first calculated for each part of the country, which were then summarized at the national level. Thus, if a disproportionate number of weather stations are located in a small area, their number does not affect the national average. There are 8 stations in Switzerland itself. In 4 cases, neighboring but nearby weather stations were also used to obtain more accurate values.