Tesla is slightly misleading.
Truckee is near Lake Tahoe, which is even higher, colder, and gets even more snow. Tahoe is also shared between Nevada and California.
In either case, there are many installations where the breakers are outside - especially where mobile homes and RV's are connected to pedestals.
It is true that the farther breakers are from the 'calibration' temperature, the less their performance matches the curves. Heat makes them trip sooner, cold slows them down - just like derating wire.
Of greater concern, IMO, are conditions that might lead to moisture condensing within the breakers.
Keep in mind that most of Alaska is a maritime environment, rather than arctic.