Thanks to the passage of cars during the day my road is now solid ice end to end. Riding up it on the 69er was an interesting experience with the Small Block 8 clad rear wheel spinning at every opportunity.
Once home I finally managed to break into the car, and unable to find my tube of silicon grease gave the seal on the bottom of the drivers door a healthy coating of GT-85 in an attempt to stop it freezing solid again overnight. I still can’t open the passenger door though. According to the climate control gubbins in the car, it was -2.5oC at 16:30, although I suspect that the thick layer of snow over the car may be insulating it from the worst of the cold.