Two major wildfires broke out yesterday (02.07.2025) in Halkidiki and Crete, where firefighters are still battling flare-ups. Despite occurring around the same time, these fires exhibited significant differences in behavior and dynamics. The Flame pyrometeorological team from the Meteo unit of the National Observatory of Athens analyzed both events, focusing on their contrasting characteristics and visual appearance.
In Vourvourou (Sithonia, Halkidiki), the fire ignited in an area with dense and extremely dry vegetation. The heat generated by the blaze was intense enough to overcome the weak winds blowing at the time, leading to the formation of a shallow and nearly vertical convective column. Fires displaying this pattern are classified as pyroconvective. Their spread is dictated by powerful updrafts created by the intense combustion of vegetation—or more simply—by the weather they create themselves. This results in dynamic and often unpredictable behavior, including sudden changes in direction and intensity.
Conversely, conditions in Ierapetra (Lasithi, Crete) were completely different. The fire started in an area with low vegetation while strong northern winds were blowing. According to Meteo, the wind’s strength surpassed the power of the heat released by the burning vegetation, causing the fire to be entirely wind-driven. Smoke spread almost parallel to the ground. These types of fires, known as wind-driven wildfires, tend to be more predictable in spread but can move extremely fast, covering large distances in short periods.
These two cases, though occurring almost simultaneously, remind us that wildfire behavior depends on the interplay between two forces: the intensity of the fire itself and the strength of the wind. When the fire’s energy dominates, it creates its own weather system (pyroconvective fire). When wind prevails, the fire follows its direction (wind-driven fire).
This distinction also means that fire danger isn’t just a single number. The same risk level could lead to vastly different outcomes depending on local pyrometeorological and vegetation conditions. Understanding these nuances in real-time is crucial for effective wildfire response and preparedness.