Buckets of rain poured down on Canton Graubünden and Canton Zurich overnight, while hail drops the size of golf balls fell amid powerful gusts of wind.
In Zurich, the whirling storm raged for half an hour with heavy rain hitting windows almost horizontally during a crescendo of exceptionally long flashes of lightning.
"Outside the window, there was a white wall of rain and hail. You could not even see the road. And it flashed almost continuously,” reads one comment from a reader on the online version of the 20 Minuten daily, which dedicated a special section to videos and photographs from the storms.
Trees fell on cars and blocked traffic in various parts of the country, reports said. A 35-year-old woman in a barbecue area near the Cresta Lake had a narrow escape when she found herself in the middle of two falling trees, said a report by the Corriere del Ticino newspaper. She was hit by a branch on the head but was not injured.
The weather also caused heavy disruptions to the rail network.
In the Bernese Oberland, a fallen tree blocked rail traffic for hours and 64 people had to be evacuated by helicopter from the Schynige Platte. In Interlaken, near Bern, a ten-minute period saw as much rainfall as is normally recorded in the entire month of April, said MeteoNews.
The storms came after another storm caused about 10 million francs ($12 million) worth of damage in the Appenzell region. The army was summoned to the area to help fire fighters clean out the streets, the Corriere del Ticino said.