I have a multiprobe engine analyzer, and at normal taxi power the CHT's are
in the low 200's on a normal day, let alone when it's around zero outside.

Even though the plane's in a heated hangar, I still may use the Tanis
heaters on very cold days to help heat the oil, but I was looking for other
possible reasons to open the cowl flaps other than responding to a knee jerk
reaction or simply a matter of routine.