-EDIT- nvm i just reread, seems i jumped the gun your temperatures are perfectly fine, if you want to reduce them more then continue reading this message :
To properly answer this question and alleviate your problems im going to need to know a few things,
1) Model of CPU and Age
2) Heatsink model (Stock or Custom)
3) Can you hear audible noise from the CPU fan?
4) Have you ever reapplied thermal paste to your CPU and Heatsink?
5) What GPU are you running and where is it in relevance to your CPU?
Also as an added extra what settings are you trying to run Watchdogs on?
The reason i am asking so many questions is because it could be a number of things, your thermal paste might need reapplied, your CPU may be taxed out, your Heatsink fan may be buggered or it could be something else entirely, only the information will shed some light on this situation
I look forward to your reply so i can help you get back on watchdogs