At least with your temps, I sure would not worry about that. I don't think an 'empty' HD rack will affect air flow in any significant manner. I use CoreTemp for my real time - since you also live in the upside down part of the world and you are now in the middle of Winter, assuming you don't have windows open, your temps are excellent but not suspiciously so. If they start getting close to 70° I go into panic mode, inspect to ensure all fans are still spinning and I then tear down my system to lug outside for blasting with my air compressor (the best way by far - with a suitable inline moisture and particulate filter, of course). In fact, my 'reminder' that it is time to clean my dust/dog hair filters is when they touch and stay above 60° for more than a couple seconds. But that drops almost as quickly back to the mid 30s. My i7 with OEM cooling sits in mid 30s when loafing along but can almost instantly jump into the mid 50s when pushed, and actually hits about 62☌ for a couple seconds during boot when I load up a bunch of stuff. I realize you live in the upside down part of the world, but is the room your computer sits in that cool? The Laws of Physics and thermodynamics just don't allow it. Click to expand.I am not sure I would trust that as 16° C = 60.8° F and it is a physical impossibility for conventional cooling (fans) to cool an object cooler than the ambient temperature of your room.

Speccy cpu temp wrong