Even at wind speeds exceeding 150 km/h and at temperatures below -40° C, the interior usually maintains a cosy -15° C. This is warm enough to have a good sleep in the thick sleeping bag. Unfortunately it is not warm enough to keep the gear from freezing. In the "morning", socks, woollen hats, toothpaste, sun screen and water bottles are frozen solid. Everything that needs to stay warm has to go into the sleeping bag. Yet the water bottle even froze inside my sleeping bag because I kept it outside of the fleece liner.