The mercury hit 20.9°C (69.6°F) in the town of Delémont in canton Jura in northwest Switzerland.
The previous January high north of the Alps had been 19.4°C, recorded on January 12, 1993 in Lucerne. The highest January temperature ever recorded anywhere in Switzerland was 24°C, recorded in Locarno-Monti (2007) and Lugano (1944) in the south of the country.
MeteoSwiss said the record January temperature in Delémont was caused by warm winds from the southwest combined with the Föhn wind – a dry, warm, downslope wind – coming off the Jura mountains.
Other locations saw balmy conditions on Sunday. In Vevey on Lake Geneva, people queued for ice creams, while in Geneva swimmers enjoyed the traditional New Year’s Day dip in the lake with fancy dress and champagne.
In the Rhine Valley of St Gallen and in Liechtenstein, it was also warm on Sunday (18.5°C in Bad Ragaz and 20°C in Vaduz).
A January record high was also set in Altdorf, canton Uri, where the mercury reached 19.2°C on Sunday. The previous cantonal record was 18.5°C.
The mild weather in Western Europe is partly due to warm air from the Atlantic east of the US state of Florida. A similar phenomenon occurred last year, SRF Meteo said.
More
More
Tempting solution: cool the planet artificially
This content was published on
Emissions continue to increase, despite promises by governments and international agreements. So why not try tinkering with the climate itself?
This content was published on
The latest figures from the Federal Office of Public Health show that lab-confirmed cases dropped from nearly 2,340 to under 2,000 last week.
Swiss cities targeted by Russian hackers during WEF
This content was published on
Russian hackers have targeted canton Schaffhausen and the cities of Geneva and Sierre, paralysing their websites on Wednesday morning.
This content was published on
Paul Hottinguer, a member of one of Switzerland’s most famous banking families, will face trial in Paris for tax fraud and money laundering.
Swiss man who died in Iranian prison had photographed military site
This content was published on
The Iranian judiciary said that the Swiss man who died in an Iranian prison on January 9 had been detained for photographing a restricted military site.
Swiss researchers patent new device for avalanche detection
This content was published on
The WSL Institute for Snow and Avalanche Research said it has granted a group of Swiss researchers a patent for a device to enhance avalanche warnings.
Berset discusses ECHR climate ruling implementation at Davos
This content was published on
Switzerland has submitted a report on the court's ruling in Strasbourg. Berset told Justice Minister Beat Jans that the Council of Europe is reviewing it.
This content was published on
A 27-year-old ski tourer has died in the hospital in Sion, in southwestern Switzerland, after being caught in an avalanche on Saturday.
Swiss health minister criticises Trump’s ‘rash’ WHO exit
This content was published on
Switzerland has expressed “deep” regret over Trump’s decision to withdraw from the WHO, Swiss Health Minister Elisabeth Baume-Schneider said in Davos.
This content was published on
Job vacancies in Switzerland fell by 10% in 2024, marking the first negative annual balance since the Covid-19 pandemic, says Adecco.
Swiss president meets Zelensky in Davos amid tensions with Europe
This content was published on
Swiss President met Zelensky at Davos. As Zelensky thanked Switzerland, Keller-Sutter said it's too early to discuss a new summit, awaiting Trump's actions.
This content was published on
Emissions continue to increase, despite promises by governments and international agreements. So why not try tinkering with the climate itself?
Latest summer day recorded since measurements began
This content was published on
The mercury hit 25.4°C in Chur on Sunday – the latest day ever recorded in the country with a summer temperature of more than 25°C.
This content was published on
Swiss glaciers have lost more than 6% of their volume this year. The decline smashed previous record retreats, but it was not entirely negative.
You can find an overview of ongoing debates with our journalists here . Please join us!
If you want to start a conversation about a topic raised in this article or want to report factual errors, email us at english@swissinfo.ch.