[lithocarpus]

Both humidity and temperature matter, it's a complex thing going on.

But yes I'm mostly in a dry environment doing this, I haven't tried it anywhere that was warm and humid at the same time.

It helps a lot to not seal the leftovers but let them have airflow and dry out on the surface. Sealed containers with moisture in them get nasty much faster.

[reverius42]

If the container is sealed (airtight) while it's still above the temperatures that (most) bacteria can survive at, and then cooled while sealed, it might actually do better than open-air for a while.