A hiker was killed after being fatally struck by lightning on Marmolada, the highest mountain of the Dolomites, local media reported on Sunday.
A 41-year-old Belgian tourist is believed to have died after a tree fell on his tent in the Friuli region.
A woman died in the Lombardy region after slipping on a wet hiking trial. Another woman also died in Cortina d’Ampezzo after a landslide buried her car, fire officials said on Saturday.
Local rescue authorities have reported “many victims” over the weekend. Hikers have also been warned to take weather alerts seriously.
The weather-related deaths reported on Sunday came as violent storms and mudslides raged on in northern Italy following the heatwave.
On Thursday, two pensioners died in central and southern Italy after being caught up in wildfires triggered by the heatwave and weeks of severe drought.
Rainfall in July was nearly 50 percent lower across Italy than is normal and peak temperatures have been hitting at least 40 degrees Celsius across nearly the entire country for almost a week.
The highs are not unusual but the duration and widespread nature of the heatwave is, weather experts say.