When I recently checked my coolant level when the car was completely warmed up, it was low. It was barely above the "full cold" line. The next morning morning when I checked it with the engine completely cold it was pretty much right at the "full cold" line. I don't know what to make of this. 2000 SSEi

Hmmm, I'm not sure either. But the good thing is, the level stays consistent and doesn't stay down.

By your description the level dropped from "barely above the full cold line" to "right at the full cold line". Did you mean right at the full hot line?

When It was completely warmed up, after maybe 2 hours of driving. The coolant level was just above the "full cold line", so It was almost an inch low. I let the car sit overnight and the next morning When I checked it. It was right at the full cold line, like it was full. This is the same reading Iv'e been getting maybe 5 times now. It'* low when it'* hot, like the fluid isn't expanding in the overflow, but its full when its cold, seemingly.

doesnt have to be exact, anywhere in there is close enough. as long as it doesnt appear to be disappearing

Check the level in the radiator itself when the engine is cooled down. Be sure it'* completely full.