Abstract. Climate models are often not evaluated or calibrated against observations of past climate extremes, resulting in poor performance during for instance heatwave conditions. Here we use the Weather Research and Forecasting (WRF) regional climate model with a large combination of different atmospheric physics schemes, with the goal of detecting the most sensitive ones and identifying those that appear most suitable for simulating the heatwave events of 2003 in Western Europe and 2010 in Russia. 55 Out of 216 simulations combining different atmospheric physical schemes can reproduce the extreme temperatures observed during heatwaves, the majority of simulations showing a cold bias of on average 2–3 °C. Conversely, precipitation is mostly overestimated prior to heatwaves, and short wave radiation is slightly underestimated. Convection is found to be the most sensitive process impacting simulated heatwave temperature, across 4 different convection schemes in the simulation ensemble. Based on these comparisons, we design a reduced ensemble of five well performing and diverse scheme combinations, which may be used in the future to perform heatwave analysis and to investigate the impact of climate change in summer in Europe. Future studies could include the use of different land surface models together with varied physics scheme.