Well, here we go again: forecasters in Switzerland have warned that the country faces yet another bout of heavy thunderstorms over the next few days. Weather warnings are in place in parts of the Swiss mountains, while cities are expected to be drenched in yet more rain.

Switzerland braces for another bout of thunderstorms

Over the last few weeks, heavy rain and thunderstorms seem to arrive at a rate as regular as Swiss clockwork. Stormy weather and continuous rainfall have caused major flooding and landslides, leading to hundreds of callouts for the emergency services and several deaths. The Swiss Insurance Association now estimates that storms have caused up to 200 million francs' worth of damage between mid-June and early July 2024.

Now, the Swiss government has forecast that heavy rain will sweep across the country once again, accompanied by equally severe thunderstorms. The storm will travel from west to east, hitting Geneva, Vaud and Bern in the morning, before moving across Switzerland in an arc encompassing the whole country, from Basel to Ticino. 

By the evening, the storms will arrive in Canton Zurich and eastern Switzerland, where up to 3,6 millimetres of rain are expected to fall. Temperatures on Friday are set to vary between 22 and 24 degrees celsius.

Weather warnings in place for parts of the Swiss Alps

While rainfall isn't usually a problem, previous storms have meant that the ground is heavily saturated with water. This means rain is likely to run off fields rather than being absorbed, increasing the risk of flash flooding and landslides. Therefore, Meteonews has issued a “strong weather” warning for rain in areas that have seen the most in past weeks - northern Ticino and south and western Graubünden - which is due to elapse at 6am on July 13. 

“Light weather” warnings are also in place for western, central and southern Switzerland with the exception of Valais. While there is a risk that the rain will cause isolated flooding on the banks of Swiss rivers and lakes, as things stand no area has been issued with any new flood warnings. Scattered rain showers are also forecast for Saturday.

"Last summer we often had a high-pressure system, which gave us dry weather. This year it is the exact opposite," explained Meteotest geographer Ralph Rickli. He added that moisture from the Atlantic and western Mediterranean was being propelled towards us, resulting in damp weather. "It's not postcard weather, but it's a blessing for nature and the soil."

Are there any blue skies on the horizon?

However, there may be some blue skies ahead for the soaked residents of Switzerland. Rickli noted that after Saturday “a high-pressure system (called the Biscay high) will extend from the west to central Europe. This could bring mostly dry weather for a few days.” The mercury is expected to rise to 28 degrees in some places on Sunday, giving the country the first bout of good weekend weather for weeks.

However, there will be a blip on Monday and Tuesday, when most of Switzerland will be given yet another shower. After Tuesday the weather is forecast to remain cloudy but dry.