I've been using a mod of some kind for this problem since Seasons was released for Sims2. I'm not kidding. This issue has been attached to Seasons since having weather became a thing in a Sims game. Three different iterations, all with a Seasons EP, and all three iterations need a mod because our Sims won't change back into normal clothing after coming inside. Of all the things the devs could have brought into Sims4 from Sims2 and 3, this irritation managed to sneak into Sims4. For the third time! :D The funniest part of this is, the devs have never been able to fix it. :D