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<p>Ensemble simulations with the Terrestrial Systems Modelling Platform (TSMP) covering northwestern Germany are evaluated for three summertime convective storms using polarimetric X-band radar measurements. Using a forward operator, the simulated microphysical processes have been evaluated in radar observation space. Observed differential reflectivity (<span class="inline-formula"><i>Z</i>_DR</span>) columns, which are proxies for updrafts, and multi-variate fingerprints for size sorting and aggregation processes are captured by the model, but co-located specific differential phase (<span class="inline-formula"><i>K</i>_DP</span>) columns in observations are not reproduced in the simulations. Also, the simulated <span class="inline-formula"><i>Z</i>_DR</span> columns, generated by only small-sized supercooled drops, show smaller absolute <span class="inline-formula"><i>Z</i>_DR</span> values and a reduced width compared to their observational counterparts, which points to deficiencies in the cloud microphysics scheme as well as the forward operator, which does not have explicit information of water content of ice hydrometeors. Above the melting layer, the simulated polarimetric variables also show weak variability, which can be at least partly explained by the reduced particle diversity in the model and the inability of the <span class="inline-formula"><i>T</i></span>-matrix method to reproduce the polarimetric signatures of snow and graupel; i.e. current forward operators need to be further developed to fully exploit radar data for model evaluation and improvement. Below the melting level, the model captures the observed increase in reflectivity, <span class="inline-formula"><i>Z</i>_DR</span> and specific differential phase (<span class="inline-formula"><i>K</i>_DP</span>) towards the ground.</p> <p>The contoured frequency altitude diagrams (CFADs) of the synthetic and observed polarimetric variables were also used to evaluate the model microphysical processes statistically. In general, CFADs of the cross-correlation coefficient (<span class="inline-formula"><i>ρ</i>_hv</span>) were poorly simulated. CFADs of <span class="inline-formula"><i>Z</i>_DR</span> and <span class="inline-formula"><i>K</i>_DP</span> were similar but the model exhibits a relatively narrow distribution above the melting layer for both, and a bimodal distribution for <span class="inline-formula"><i>Z</i>_DR</span> below the melting layer, indicating either differences in the mechanism of precipitation formation or errors in forward operator which uses a functional form of drop size distribution.</p> <p>In general, the model was found to underestimate the convective area fraction, high reflectivities, and the width/magnitude of <span class="inline-formula"><i>Z</i>_DR</span> columns, all leading to an underestimation of the frequency distribution for high precipitation values.</p>