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Taking advantage of a large ensemble of Convection Permitting‐Regional Climate Models on a pan‐Alpine domain and of an object‐oriented dedicated analysis, this study aims to investigate future changes in high‐impact fall Mediterranean Heavy Precipitation Events at high warming levels. We identify a robust multi‐model agreement for an increased frequency from central Italy to the northern Balkans combined with a substantial extension of the affected areas, for a dominant influence of the driving Global Climate Models for projecting changes in the frequency, and for an increase in intensity, area, volume and severity over the French Mediterranean. However, large quantitative uncertainties persist despite the use of convection‐permitting models, with no clear agreement in frequency changes over southeastern France and a large range of plausible changes in events' properties, including for the most intense events. Model diversity and international coordination are still needed to provide policy‐relevant climate information regarding precipitation extremes. Plain Language Summary: Despite growing computational resources and multiple model developments, projecting future changes in the high‐impact Mediterranean Heavy Precipitation Events remains both a numerical and scientific challenge. The present study takes advantage of the recent availability of a relatively large ensemble of high resolution Regional Climate Models (2–3 km), which represent a step change in the simulation of precipitation extremes, and of an object‐oriented approach, allowing us to track the convective precipitating systems on an hourly basis. Looking at future changes in fall Mediterranean Heavy Precipitation Events at high warming levels, we identify a robust multi‐model agreement for an increased frequency from central Italy to the northern Balkans combined with a substantial expansion of the affected areas, and an increase in intensity, area, volume and severity over the French Mediterranean. However, considerable uncertainties remain in terms of frequency over parts of the domain arising from uncertainty in changes in large scale weather patterns, and in terms of degree of intensification for the most intense events. It suggests the need for model diversity and for more coordinated high resolution climate projections with careful selection of different driving global models in order to provide policy‐relevant climate information regarding precipitation extremes. Key Points: High‐resolution ensemble and object‐oriented approach offer a unique opportunity to study changes in Mediterranean extreme precipitationRobust agreement is found for an increase in intensity, volume and severity for future French Mediterranean Heavy Precipitation EventsEven at convection‐permitting scale, considerable uncertainty remains regarding the degree of intensification of the most extreme events [ABSTRACT FROM AUTHOR]

The Mediterranean region of France are regularly affected by extreme precipitation that often lead to devastating flash-floods, often associated with both human and material damages. The evolution of such events in terms of occurrence and severity with climate change remains an open question.The purpose of the current study is to characterize the future evolution of these heavy precipitating events in terms of occurrence and intensity. A historical simulation (1976 – 2005) will be compare to a future simulation (2071 – 2100) for the RCP8,5 scenario. The CNRM-CM5 global climate is used as driver model. The study also compare climate change simulations from a convection parametrized convection model (ALADIN-Climate) and a convection permitting reginal climate model (AROME-Climate). These simulations were carried out on the domain defined by the CORDEX Flagship Pilot Study "Convective phenomena at high resolution over Europe and the Mediterranean". It is centered on the Alps. This domain allows a good representation of the large scale circulation over the Mediterranean sea that causes convective phenomena in the Southeastern France. The study of changes in spatial distribution and cumulative precipitation will be based on daily and hourly averages and quantiles of precipitation.I would like to share my knowledge on convection permitting regional climate model with interested people. This workshop would be a great opportunity and I hope, I will have the opportunity to exchange with people from this community. [ABSTRACT FROM AUTHOR]