A recent increase in the rate of failure in periglacial rick walls has been attributed to permafrost degradation. To validate this hypothesis, we applied a simple transient thermal model to hundreds of observed rockfalls in the Mont Blanc massif and determine the statistical relationship between rock wall temperature dynamics and failure occurrence. This is a first step towards prediction of rockfall probability. To improve our understanding of the processes leading to failure, we made a first attempt to cpuple thermal and hydrological models.The role of water flowing through bedrock fractures enhances the rate of permafrost degradation and affects the pressure field distribution.