On May 31, people near the city of Thun, Canton Bern were treated to one of nature’s most impressive sights. Onlookers around the local lake were able to capture a tornadic waterspout making its way across the waves, reaching up to 100 metres high.
“There was a rumble of thunder…when my wife looked at the lake, she saw the waterspout", one witness told 20 Minuten. The twisting tornado-like jet emerged from the water late on Wednesday, much to the amazement of onlookers on the banks of Lake Thun. Areas of the lake were absolutely drenched with water as the tube passed them.
While it proved a magnificent sight, especially with the Swiss mountains in the background, the gravity-defying spout only lasted for a few minutes. "I've lived here for over 20 years, but I've never seen anything like it," the witness concluded.
Waterspouts of tornadic waterspouts are caused when warm air meets cold weather. Instability in the atmosphere where the two temperatures meet can cause air to rotate, creating a cyclone effect. If this happens over water, the phenomenon can cause a waterspout - however, you shouldn’t confuse them with tornados as they can take place at much lower wind speeds.
One meteorologist told 20 Minuten that waterspouts are unpredictable as they can happen at any time and only last for a few minutes, although they are exceedingly rare in Switzerland. While more harmless than tornados, they can still cause issues, especially for smaller boats.