Unseasonably stormy weather moved eastwards across northern Italy as intense rain and 100km/h (62mph) winds battered the region.
In some places, tennis ball-sized hailstones injured people, damaged cars and uprooted trees.
A 16-year-old girl was killed when a tree fell on the tent she was sleeping in at a summer camp near the city of Brescia, while a middle-aged woman died after also being hit by a falling tree in Lissone, north of Milan.
The mayor of Milan, Giuseppe Sala, said: “I have never seen anything like this… We can’t deny it any longer – climate change is changing our lives.”