Another cold climate question. 'Scattered Frost' seems to be a popular description that shows up in the forecast description. The description seems a little odd given that it is being output when the temperatures are well below freezing. In fact down into the -20s C. Scattered frost is an understatement at those temps.

Would it make more sense to have such a description appear only when temps are expected to 'approach or go just below the freezing level? Also, it would also seem to make sense to tie it to the average temps for that location/date. If the average low temp is -15-20 C, a scattered frost description seems redundant regardless of the forecast temp.
Just something for consideration. Thanks.