Not sure what's wrong with the grass. It's starting to turn brown and almost looks dead at the ground level.

Its been a bumper crop for chinch bugs this year. May need to do a test

Looks like Take All Patch. If you can easily lift the grass, that's what it is. It might be a fungal problem too.

Pretty safe to say it is a fungal problem with all the rain. Hit it with a product called F-Stop and follow up again according to the label.

Brown patch maybe? Would make sense with all the rain and wet conditions we've been having.

Could also be chinch bugs. to test take a coffee can or similar with both sides open, stand it up on the grass and fill with water to the top, if you see a bunch of small bugs floating on the surface then its chinch bugs, if not its something else.

Thanks!

Here's a photo of chinch bugs. No need to put insecticide down if you don't see these guys.

That being said, this doesn't look like chinch bug damage, primarily it hasn't been hot enough for them to show up in full force. I'd still do the coffee can test to be sure. Also, use a liquid insecticide to treat them, and you'll have to do it at least three times to break the cycle.