For me personally, comfortable frosts pass at temperatures down to -18°C.

For me, there is no such thing as a comfortable frost. My hands are in pain in and under -7 °C, even in gloves. And the temperature often go below -20 °C in my country (in Hungary) in the winter. The record cold is currently -35.50 °C, and this was on 2021.02.13. I am still looking for wool gloves in my area, but I have not found any. At least not that I could afford. But a 100% wool glove would probably greatly help in the cold.

Merry Christmas.

Have a nice day. All the best. Greetings and much love from Hungary.