🇨🇭Switzerland

Switzerland is a landlocked alpine heart of Europe spanning 45°49′–47°48′N, organized into three macro-regions: the Jura in the northwest, 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 sees January highs of 4°C and lows of −1°C and July highs of 24°C with 1,090 mm of evenly distributed rainfall; Lugano on the southern Alps is milder Mediterranean-influenced (highs of 7°C in January and 27°C in July, 1,560 mm); Davos at 1,560 m is markedly colder (January lows of −9°C, July highs of 19°C); Säntis at 2,500 m and Jungfraujoch at 3,500 m average below freezing over the year. 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 hottest July afternoons are in Geneva, with average highs around 24.8°C, while Bern has the coldest January nights, with average lows 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.