EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Climate change has increased the intensity of documented Derecho storms in France

Lucas Fery1,2, Bérengère Dubrulle2, and Davide Faranda1,3,4
Lucas Fery et al.
  • 1Laboratoire des Sciences du Climat et de l’Environnement, CEA Paris-Saclay - Orme des Merisiers, UMR 8212 CEA-CNRS-UVSQ, Université Paris-Saclay & IPSL, Paris, France (
  • 2SPEC, CEA, CNRS, Université Paris-Saclay, Paris, France
  • 3London Mathematical Laboratory, London, UK
  • 4LMD/IPSL, Ecole Normale Superieure, PSL research University, Paris, France

A thunderstorm system formed during the night of August 17 to 18 over the northern Balearic Islands and moved rapidly to the northeast, causing widespread damage over Corsica, Northern Italy and Austria due to the production of strong surface wind gusts (>200 km/h over Corsica) and severe hail. The intensity of this phenomenon can be classified in the category of derechos: this is a classification of very violent storms that takes into account the wind gusts (more than 94km/h with maxima of more than 120km/h) and the extent of the affected territory (major axis longer than 400 kilometers). Here we analyse recent derechos event in France in the satellite era and assess the role of climate change in modifying their characteristics. We identify eleven events in the past and provide their tracks retrieved using the ERA5 reanalysis dataset. To detect climate change signal, we compare  analog cyclonic atmospheric circulations that can lead to derechos in the distant past (1950-1979) and in the recent past (1992-2022). Two of the events, the derechos which affect the Northern regions are unprecedented, that is no good analogues can be found and attribution statements cannot be made on the basis of the present analysis. For the other events, instead, we find a significant signal of increased precipitation in the recent period which, without change in circulation, is explained by the higher temperatures of the Bay of Biscay and the Mediterranean Sea. For these events there is also not a clear change in depth of the pressure minimum which triggered the convective system. Finally, we can exclude the role of the climate variability of El Nino (ENSO) in most of the events, while we cannot rule out the influence of the Atlantic Multidecadal Oscillation (AMO) in favoring low pressure systems possibly leading to derechos.

How to cite: Fery, L., Dubrulle, B., and Faranda, D.: Climate change has increased the intensity of documented Derecho storms in France, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-15502,, 2023.