DISCUSSION: As a very large and intense thunderstorm event erupted across parts of Western and Eastern Europe yesterday afternoon and evening, many of the storms exhibited particularly high amounts of lightning strikes (i.e., a combination of cloud-to-ground, cloud-to-cloud, and intercloud-type strikes). As seen in the graphic below courtesy of lightningmaps.org, there was especially impressive lighting strike density observed across Eastern/Central Spain, Southern France, and several countries just north and east of the Eastern Mediterranean Sea.
As a further explanation, cloud-to-ground lightning occurs as a result of a disproportionate concentration of positive and negatively charged particles in the atmosphere located above and close to or at the ground respectively. This differential in the nature of the electric charge between the cloud-base and the region close to or at the surface results in an electrically-based energy imbalance which in sufficient quantities can result in a discharge in the form of an electric discharge from the cloud and down towards the surface.
Cloud-to-cloud lightning occurs as a result of differentiation in the charges of the particles between nearby clouds associated with intense thunderstorms. As a result of the very intense thunderstorms being close proximity to one another coupled with the strong differential between the positively and negatively charged particles between the respective cloud bases, this can often trigger what we observed as cloud-to-cloud lightning.
Intracloud lightning occurs based on differential in the location of positively and negatively charged particles within an intense thunderstorm (which is often positioned fairly high above the ground and is also referred to as being an elevated thunderstorm). As a consequence of the strong gradient created by the stronger concentrations of positively and negatively charged particles within different parts of the thunderstorm, this electrical in balance with in a thunderstorm cloud often triggers what we observe as intracloud lightning.
To learn more about this and other high-impact weather events from across Europe, be sure to click here!