You don't say where you live or the type of grass you have. Do you see leasions, spores, discoloration? Does the turf pull up easily? Is there a certain time when you see the spreading? Do you see moth like bugs? What do you fertilize with and when? What watering schdule do you use? Can you shove a screw driver into the areas more easily into these areas than other areas? Have you gotten a soil test?

Sorry!

i live in West Michigan. Pretty sure that's kent. blue grass? I don't see any discoloration besides the yellow, deadened grass spots. Last summer I did have some dollar spot, but I don't see evidence of that now.

I haven't noticed any time that this happens more so than others. My lawn service stated that it was most likely the dollar spot last year, sprayed for it, and said that it should rebound this spring. It hasn't.

The lawn service I use fertilizes 3-4 times a year, normal times (holiday schedule) and uses "slow release" fertilizer, whatever that means.

I usually water 2 times a week, for an hour or so each zone. More or less depending on the rain.

I will check the screwdriver test later today, and no, I have not gotten a soil test.

I apologize for the lack of info. I was kind of hoping someone would see the pictures and recognize an issue right away. Thank you all for any help you can offer though, as this is starting to get frustrating!

1. You want to determine if you have an active problem. Is it disease? You will need to get down and look at the blades of growing grass that boarders the troubled areas. Look for lesions, spores, dusty residue. (google lawn diseases for help and images). 2. Is it insect damage? It's a bit early in the year for it. See if the grass pulls up easily, like a toupe, look for bilbugs and web worms. (once again google grass insects, bilbugs grubs etc. for assistance.)
If you find active disease (or insects) identify it and apply an appropriate herbicide or insecticide. (once again google will help you match the cure to the problem).
If no active problem exists, move on to repair.
Bare soil absorbs heat and will adversly affect surrounding grass, much as grass next to concrete is affected by the heat. Move on to repair.
Some soil areas become hydrophobic. Apply 3 oz/k sq ft of shampoo like White Rain to the lawn using a hose end sprayer.
If you have an abundance of KBG, you should have seen some spreading into the damaged areas this Spring. As you indicate that the areas seem to be getting larger, you probably have more fescue or rye. Once either of them die, the survivors don't spread in. You'll need to reseed to get grass.
Repair:
Grass that is not getting the nutrients it needs is very sucepable to diseas, insects, heat and drought. Trying to grow grass in soil that is nutrient deficient is a frustrating exercise in futility. Trying to guess what needs to be applied is a fools errand and expensive AND can cause more damage. For less than the cost of a bag of fertilizer, you can get a soil test that will tell you what nutrients you have and what you may need. Well worth the money--measure twice and cut once. www.loganlabs,com iw one of the best. Once you know what is missing, correct it, and plant your seed this fall.
Good Luck.