Got the hots for something long...but it's like a freakin sauna out? I feel you. In fact, I feel you so much because that's my life #hood. When it's time to dress for this weather, it can get confusing. You go from a relatively nice climate in your house, to a goddamn BBQ in your car, to an igloo in your car at the end of your commute, to ballsweat outside again until you comfortably install your butt in your office chair only to turn into Olaf from Frozen 2 seconds later for the rest of the day. Sounds familiar?
So... you can't go in a swimsuit and you can't go naked (trust me, I've asked). You need something that can be rolled up for outside and rolled down for indoors. Keep it loose so nothing sticks to your sweat. No one will even know you're sweating! Except if you have a Ron Burgundy of a sweat mustache. Then I can't help you. Antonacci...OUT!
blouse: Madewell (old) - find similar here
pants: c/o Ardene
denim shirt: Topshop (old) - find similar here