The maximum of 30.2C was recorded in Sion just after 4pm. This was just the fourth time Sion has seen temperatures above 30C in the second half of September, according to SRF Meteo.
Temperaturen ? «klettern» in die Höhe: Aktuell über 30 °C gemessen in Sion/VS. Ein #Hitzetag in der zweiten Septemberhälfte gab es seit Messbeginn in Sion erst 4 Mal. #hitze #altweibersommer #phrasendreschen ☀️ ^ng pic.twitter.com/2aeoLuW9Mt
— SRF Meteo (@srfmeteo) September 16, 2019
Valais was not the only part of the country to see warm weather on Monday. Across north-western Switzerland, temperatures of 29C were registered.
Maximums of over 30C are rare in Switzerland in the second half of September, but not unheard of. However, the Italian-speaking canton of Ticino has gone one better: on October 24th last year, Locarno saw a temperature of 30.5C.
Conditions are expected to be cooler in eastern Switzerland on Tuesday, although maximums of 28C are still possible in the south and west of the country.
The second half of the week will be generally cooler although things are looking good for a warm and sunny weekend to come.
Switzerland had its third hottest summer on record in 2019 thanks in part to two heatwaves that hit the country in June and July.