According to Wikipedia humidity is the amount of water vapor in the air and water vapor is water in gaseous form, it's invisible. When we got up this morning to do our walk it was only 72º, wonderful, down right balmy. So we quickly dressed and hurried out the door, we always walk before breakfast, it's generally cooler. And cooler it was, but oh was it humid. We had heard someone describe the air as grey and leaden and that's exactly what it was, not a breath of air. You could feel it sitting on your eyebrows, my sinus's hurt so much my teeth ached.
By the time we finished our walk I was drenched in sweat. Hurrying through the house I didn't even look for my swimsuit I just peeled my clothes off as I went and wearing only my underwear I jumped in the pool which was really quite cool, no it was cold and it felt wonderful.
I should say that we have no near neighbors and our yard is screened by trees all around so our backyard is very private.
When I got out of the pool and dressed I looked the humidity level up on the 'net and it was 100%, any more and it would have been raining.
It stayed that way all day and finally it started raining about a half an hour ago. That will cool things off for a little while, but then it will just get steamy. Summer time in the south.