Local snowpack measurements and local stability tests are currently the basis for the assessment of snowpack stability in most avalanche warning operations. The SnowMicroPen (SMP), a high-resolution penetrometer for snow, measures penetration resistance of snow. In order for SMP measurements to be useful for stability evaluation (or avalanche forecasting purposes), stability information needs to be derived from the SMP signal. It was shown that structural and mechanical parameters derived from the SMP signal for known (or manually observed) failure interfaces were related to snowpack stability. The dataset contained 66 parallel SMP and manual snow profiles with stability tests from five winter seasons 2001-02 to 2005-06 in Switzerland. It was balanced between stable (35) and unstable (31) profiles. The manual failure layer determination in the SMP signal was improved. Micro structural and mechanical parameters were derived from the SMP signal using two models describing the interaction of the SMP tip with an idealized snow structure. The parameters from the improved model are compared with snow stability data for the first time. The new model slightly improved the results of the statistical analysis and the classification accuracy of a failure interface from a SMP profile. The analysis confirms the potential of the SnowMicroPen operational use in avalanche forecasting services.