A state of emergency was declared on Tuesday night in Casargo, a town in the mountains to the east of Como, after heavy rain caused the Varrone river to burst its banks for at least the second time this summer.
Mountain rescuers, firefighters and other emergency services worked through the night to move people to safety.
No injuries were reported, though torrents of mud caused damage to property, overturned and swamped cars and blocked roads.
Italian agricultural association Coldiretti said farmers raising goats and cows above Casargo were cut off due to blocked roads.
Meanwhile, mudslides, thunderstorms, hail and gales were also reported in the Alps further east.
In the South Tyrol capital of Bolzano, where winds of up to 72 km/h were reported and 27 millimetres of rain fell in just 20 minutes, authorities said it was the worst storm on record since June 2008.
Between heatwaves and freak storms, Italy has had several months of extreme weather that have already left several people dead and caused millions of euros worth of damage to the country’s agriculture.