Severe thunderstorms developed around Genoa, Italy in recent days, with lightning strikes reaching the ground even away from the thunderclouds, an event known as positive ground flashes.

Positive ground flashes are relatively rare: only around 5 to 10% of all ground flashes are of this type. They usually originate high up in the thundercloud and can travel an astonishingly long distance from there.

For example, a bolt of lightning can strike many kilometres away from the actual thunderstorm – even in dry conditions. The images from the Gulf of Liguria near Genoa illustrate this impressively.

This means that there may still be a risk of lightning, even if the storm clouds seem a distance away and there's no rain falling in the area. The LightningRadar shows at a glance recent strikes so you can stay alert to lighting around you.

Positive ground flashes are also dangerous because they can reach particularly high current levels. As a result, they are often significantly more powerful than ordinary negative ground flashes. They occur mainly during severe thunderstorms.