In what is the coldest morning of this winter to date, the temperature in Zurich was -10.6C at 6am on Monday, while Bern was not much warmer at -9.4C. In Geneva the thermometer was at -6.2C, according to MeteoNews.
Maximum temperatures on Monday will be between -10C and -3C degrees but the wind chill factor will mean it will feel between 10C and 20C colder, the weather service reported.
The current cold snap is expected to last until Wednesday with temperatures slowly climbing after that and reaching a spring-like 10C on the weekend.
The freezing conditions across much of Europe at the start of this week are related to what is known as a Sudden Stratospheric Warming Event above the North Pole, according to World Meteorological Organization. This has resulted in freezing easterly winds sweeping into Europe from Siberia.
It also means that temperatures in Switzerland are far below those in the Arctic Circle where conditions are up to 25C are warmer than usual for this time of year.
Authorities in Geneva and Lausanne reacted to the intense cold over the weekend by laying on a combined extra 580 beds emergency beds. In German-speaking Switzerland, many cities saw patrols with homeless people offered a place in a shelter or a winter sleeping bag.