Unless you are in a VERY cool room, a cpu temp of 16c is most likely not accurate anyway.
Since the built in cpu sensors are designed to throttle a cpu and shut it down in case of overheating, they are not always accurate at low temperatures.
Because HWmonitor and other software monitoring is designed for a wide range of hardware getting some irregular readings is not uncommon. These software packages read various sensors common to many boards and not all boards use all the inputs. This is a common reason for errors like 128c or other super high temperatures as well as seeing 12 volt rails reading 1 volt or some other random value.
Because of all this variety, the software does not know if it is seeing a cpu temperature or a chipset, vrm or other are of the board.
Your board may have its own software to compare to the third party software you are running. Most board software will not read the same core temps(socket/LGA or another on die sensor is common).