Looks like the start of fungal disease in your lawn.

I kind of wondered about that because fungus is something we deal with every year. Thanks!

What zone are you in? You're mower is cutting clean so that's not a problem. How often do you wash it?

We live in Omaha, Nebraska. We water 1/2 inch, twice a week.

so 5a about

Maybe just do some organic dish washer soap with you're next watering .

I would recommend you spray a fungicide, left unaddressed it will wipe out your entire lawn. Bayer Advanced Fungus Control works for many people and can be found at Lowe's etc.

You don't need a fungicide, that is half dormant bermudagrass.

Joneboy what do we do about that?

I have no idea why we would have bermudagrass.

Holy crap. Bermuda grass needs LOTS (monthly) of fertilization to maintain a deep green color. If you have bermuda that could be those light green areas in your yard. There were limited close up pictures and no one would even think about bermuda in Nebraska.

With the limited warm weather, bermuda would not spread far before going dormant in the Fall. Do those areas turn brown before other areas of your lawn?

Have you done any treatments to your lawn recently? Can you provide close-up pictures of the grasses in the the light green area of your lawn?

Can you rake the area? Are there stolons (long vine-like things)?

Forgot - there does seem to be areas of disease in 2 of 3 pictures.

There's no bermuda anywhere in this thread. The first picture is clearly dead fescue. While I encourage everyone to provide input let's try to be responsible about the info we provide, it may cost someone their lawn.

You can see stolons in the first picture and roots at the nodes. No bermudgrass in Nebraska is not typical, but I'm sorry that is certainly not fescue or bluegrass or any other cool season grass. If you want to be responsible be able to identify a disease before suggesting that they use a fungicide. I would also like the original poster to post a couple more pics of the grass in question if it's not to much trouble.

Here are a couple more photos. Whatever it is, if I rake it up and re-seed with KBG this fall, will that help? I did put down a fungicide because there are definitely areas of fungus in some areas.

IF, IF, IF, if it is bermuda you will know when you take a rake to it. I'm not debating whether it is or not, that's above my pay grade. If it is bermuda, just raking and overseeding will not get rid of it. You will need to take 4-6 weeks of repeated glyphosate treatments to get it under control. Even then there is no guarantee of success because dormant bermuda laughs at that stuff. You need a definitive grass type identification to handle the situation properly or it may cause unwanted lawn damage as stated by j4c11.

On a good not, your mower blades are in pretty good condition - nice and sharp.

I cannot tell you what it is, but I have the same condition in my lawn as that in your first photo showing the straw like grass laying on a dark wood background. I live in Illinois just southwest of Chicago. My lawn in primarily Kentucky Bluegrass. Last year, I power raked for the first time in 15 years, so I wonder if I brought something in. I also had fungus in that area of my lawn last Fall, which I left untreated and then I overseeded this Spring.

I just noticed that this issue was posted last July (2016). If you see this post, I would be interested in whether you ever identified the problem and whether you were able to eliminate it.