The representation of thunderstorms (deep convection) and rain showers in climate models represents a major challenge, as this process is usually approximated with semi-empirical parameterizations due to the lack of appropriate computational resolution. Climate simulations using kilometer-scale horizontal resolution allow explicitly resolving deep convection and thus allow for an improved representation of the water cycle. We present a set of such simulations covering Europe and global computational domains. Finally, we discuss challenges and prospects climate modelers face on heterogeneous supercomputers architectures.