Cooler weather makes me want to wear more jewel tones. While the weather isn’t that much cooler, the fact that it is September makes me want to think Fall. A few more weeks and it will technically be Fall so that works.
I like the option of a more sheer blouse with a neutral cami. I hate hate HATE when people just wear sheer blouses/tops/etc but that is a rant for another day. A sheer blouse can also work with a sweater or jacket when it gets even colder.