what temperature would it need to be to wear a cardigan and a woolen coat over the top?

First things first - I was just wondering if I was going to wear a short sleeve shirt then a long or short collard shirt over the top then a button cardigan ( probably unbuttoned ) with a woolen coat over the top with a scarf with gloves, that's probably a lot to wear, so I was wondering what temp would I need to be outside for that type of clothing?