Since Snowy Escape Sims are dressed in cold weather gear upon game start up
As the title says there's an answers HQ thread https://answers.ea.com/t5/Technical-Issues-PC/Sims-wearing-cold-weather-gear-after-Snowy-Escape/m-p/9736084#M195456
Forum Discussion
Yeah, last night my Sims wore their winter wear in the house, gloves and hats and all, but went out in the snow in bathing suits.
