🇨🇭Switzerland

Switzerland is a landlocked alpine heart of Europe spanning 45°49′–47°48′N, organized into three macro-regions: the Jura plateau in the northwest (~700–1,200 m), the central Mittelland plateau holding most population (Zürich, Bern, Lausanne, ~400–600 m), and the Alps covering ~60% of the territory and rising to 4,634 m at Monte Rosa (Dufourspitze). This topographic diversity produces a wide climate spectrum—humid continental/oceanic Dfb–Cfb on the Mittelland, alpine ET/EF above ~3,000 m, and a small humid subtropical Cfa pocket on the southern Ticino slopes facing the Mediterranean.

Zürich averages 0°C in January and 19°C in July with 1,090 mm of evenly distributed rainfall; Lugano on the southern Alps is milder Mediterranean-influenced (3°C / 22°C, 1,560 mm); Davos at 1,560 m is markedly colder (−5°C / 13°C); Säntis at 2,500 m and Jungfraujoch at 3,500 m sit below freezing year-round. The föhn descends rapidly off the Alps producing high winds in northern valleys. Major events include the August 2005 floods, the 2003 European heatwave (record 41.5°C in Grono, southern Switzerland), and the 2022 glacier-melt summer; Swiss glaciers have lost over half their mid-19th-century volume.

Our archive covers 6 Swiss cities with daily ERA5 reanalysis data going back to 1940. The warmest July averages occur in Geneva, around 24.8°C, while Bern records the coldest January nights near −3.2°C. Comparing the last decade against the 1940–1970 baseline, mean temperatures across these cities have risen by about 2.2°C.