It’s totally your call. For some reason the leaning against the car and wearing a sweater reminded me of Sixteen Candles, and once my brain latched onto the sweater it was stuck.
I don’t know what people wear in Ohio, but sweaters are not a thing here. But, it’s also very dry, so the cold doesn’t feel that cold, if that makes sense. My husband wears cargo shorts all year round, even when it’s below freezing.
It occurred to me that Kekoa likely would have had to purchase clothes for this trip, which might explain the choice, although I don’t think you need to get into it. I grew up and lived a big chunk of my adult life in Fort Lauderdale, so I know people who live in tropical climates don’t have winter wardrobes. I worked at a middle school for several years, and when the temperatures dropped, not only were iguanas falling out of the trees (haha), but the kids would show up to school wrapped in blankets because they didn’t own jackets/coats.
Don’t overthink it. Most people probably wouldn’t give the sweater a second thought.