I have no idea, but which direction does this section face?

It’s the more shaded side of our home, North I believe

Condensation would be my guess. Was the “stain” picture taken early in the morning? You live in a place with high humidity?

No we live in Ohio. I believe it was taken around 10:00 am

I'm betting you'll find roof framing directly under the "stains". Check the roof ventilation please.

Yes so there are trusses that lay flat and no on edge but the builder claims that it’s not uncommon to do that on a hip roof and they do that so that they have something to attach the sheeting to. I’ll upload more pics of the trusses

The arrow shows one of the boards that is flat against the sheeting

There are several vents in the attic so I wouldn’t think there would be poor ventilation

Had you had a cold night before the top picture was taken? Are those white things snow piles? Could it be that where the roof timbers touch the sheeting it is better insulated from the warmer air in the loft and would get colder at night? And therefore, as the outside of the roof warmed up in the morning, those strips would remain colder, and hence damper, than the rest of the roof? Being on the north side, the phenomenon would last longer into the day.

It's perfectly normal. The roof gets cold at night, frost or dew collect on the roof, and as it warms up and the moisture starts to melt and/or evaporate, the last part to go is where the framing is, because there's more material there to heat back up. It's especially prevalent on calm days. I'll bet you had a frost that previous night. I see it all the time here in central New York.

Frost ghosting

That makes perfect sense. My question is why would an inspector not know this? Just curious, are you a roofer or in construction?

Hi, Courtney,

You're inferring that home inspectors have more expertise than they the majority do, at least in my experience. I've never seen a home inspection report that didn't include lots of recommendations for "further investigation by a qualified fill-in-the-blank specialist."

@seabornman is this frost ghosting a cause for concern? Do you know if there is a way to fix it?

Judging by that one photo, I'd say there is no problem. If I saw that same roof with a light blanket of snow and there was uneven amounts of snow accumulating over the framing or lots of icicles at the eaves, I'd say you had an insulation issue in your attic. But either way, it has nothing to do with the quality of your roof.

"Is this frost ghosting a cause for concern?"

No.

"Do you know if there is a way to fix it?"

Talk to an insulation contractor please.