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Abstract. Small scale floods are a consequence of high precipitation rates in small areas that can occur along frontal activity and convective storms. This situation is expected to become more severe due to a warming climate, when single precipitation events resulting from deep convection become more intense ("Super Clausius-Clapeyron effect"). Regional climate model (RCM) evaluations and inter-comparisons have shown that there is evidence that an increase in regional climate model 10 resolution and in particular, at the convection permitting scale, will lead to a better representation of the spatial and temporal characteristics of heavy precipitation at small and medium scales. In this paper, the benefit of grid size reduction and bias correction in climate models are evaluated in their ability to properly represent flood generation in small and medium sized catchments. The climate models are coupled with a distributed hydrological model. The study area is the Eastern Alps, where small scale storms often occur along with heterogeneous rainfall distributions leading to a very local flash flood 15 generation. The work is carried out in a small multi-model (ensemble) framework using two different RCMs (CCLM and WRF) in different grid sizes. Bias correction is performed by the use of the novel Scaled Distribution Mapping (SDM) method. The results show, that for small catchments (< 200 km²) a resolution of 3 km is essential to accurately simulate the magnitude of flood events. Flood frequency and seasonality are both represented well in all catchments. In the larger catchments resolutions of 12.5 km and 50 km already yield statistically satisfying results, but poor results regarding 20 seasonality. Also, due to the short response times in the small sub-catchments a time step of 1 hour is required. In all setups a bias still exists in precipitation and temperature, which sometimes leads to unrealistic hydrological conditions demonstrating the necessity of bias correction. The results show the added value of reducing grid size and bias correction in climate models that can be used to model flood mechanisms in small and medium sized catchments.