Near the end of a recent flight from Australia, the plane is approaching Los Angeles International quite early in the morning and a cockpit announcement describes the conditions on the ground as "sunny with light winds and a temperature of ten degrees".
That's it. No mention of °C or °F. The pilot just assumed everyone knew what an unqualified 10° meant. And for what it was worth, he was probably correct. I did not hear a single person in my vicinity ask for clarification or conversion. (At a rough guess based on the queues at immigration the passengers were about evenly divided between Australians and US Americans).
