Is most of your lawn dead?

 

Show us the area in the lawn where you see this. How big of an area? in other words more pictures, not just a single blade.

This does look like fungus, but GLS mostly occurs in the summer months.

 

No, I hope not. I'm just seeing these lesions on some of the turf.

 

Thanks for the replies. I’ll get some more pictures this afternoon and post them here.

 

Here are some pictures that show areas typical of what I'm seeing in my lawn.

 

Not gray leaf spot. GLS appears in late summer and will kill most of your stand. Thankfully, it's not common on tall fescue and KBG is immune. It looks like that is your mix?

Your lawn looks fine to me. Maybe some brown patch and dollar spot. Some of the lesions look like they are attached to seed stalks. That's normal. I would not apply fungicide base on your pics.

In terms of when to treat with fungicide, I'd be watching humidity and low temps. Once night low temps are consistently above 65, I'd look to treat preventatively.