In many countries the ODD of an autonomous vehicle will have to include operation in a wide range of weather conditions. It is essential, therefore, that we understand how the performance of different perception sensors is affected by snow. We will present the work that has been undertaken to investigate and quantify the performance of perception sensors covering camera, radar, lidar and thermal imaging under these weather conditions. This work is part of the Sim4CAMSens project which is led by Claytex. The consortium has been awarded a £2 million grant to focus on perception sensor modelling, simulation and testing.