The Générac forest fire, south of Nîmes in the Gard department, is reaching dangerous proportions with the appearance of a pyrocumulus cloud – the sort typically associated with extremely intense wildfires, such as those seen in the United States, Canada or Australia.
Big white cloud
According to Fire Chaser 13’s explanation on his Facebook page, pyrocumulus clouds form as a result of intense heat (a fire) which, upon reaching a certain altitude, condenses to form the white cloud that we see.
If the fire intensifies, these pyrocumulus clouds can develop into pyrocumunolimbus clouds. Rain is sometimes observed upstream of this type of fire, as well as a powerful downdraft known as a downburst (a powerful gust created by the fire), which can destroy the forests upstream of the fire and help it to spread.