Adding in another vote for tights! I live in central AL and it has been 90+ and humid all weekend, blahhh. But like someone else said they do show all kinds of creases and lumps bumps etc lol. So I only ride in them when I’m at home or if I have a shirt long enough to cover my behind. A lot of workout pants at walmart or wherever have the neat thigh pockets now, have not tried to ride in them but I know the synthetic saddles have a nice grip feel to them so shouldn’t be a slippery problem.
Good luck! Maybe get you a little personal fan to wear on your neck? 
I love these:
https://www.ridingwarehouse.com/Irideon_Womens_Synergy_Knee_Patch_Riding_Tights/descpage-ISKRT.html
I don’t feel any hotter in these than in shorts.
Oh, I like these also! I stumbled upon them on Amazon and they are great. Cute, cheap, big pockets and they are holding up well.
