It’s hot outside but my dog insists on being out?

Hi all! It is close to 90 Fahrenheit in North Carolina today and my little dog refuses to come in for more than a few minutes at a time. She’s eating, she’s drinking, even playing a bit, but then goes right back outside to sun bask during the hottest parts of the day. I try to keep her inside but she whines at the door. The humidity is terrible and I’m worried. Not that anything might be wrong with her, but that she’ll suffer a heat stroke or something. I don’t understand how she can be comfortable as she’s panting lot (at least when she’s not snoozing in the sun). Should I make her stay inside more? I like it that she seems to be enjoying herself, but I can’t help but worry.