I have an old house that has both wooden and aluminum storm windows. Many of the windows develop condensation and frost on the storm windows when it's cold outside. I made sure weep holes were clear, and I've tried various approaches to sealing the interior windows to prevent condensation on the storms. While sealing has reduced the condensation on the storms, it hasn't completely eliminated it, even when following typical winter humidity guidelines.
Is there a certain amount of unavoidable exterior storm window condensation? Is some condensation okay? Is there a point at which storm window condensation would become a problem? Would it indicate that there would be condensation developing in other invisible places in the house, such as wall interiors or attic space?