Environmental factors can play a significant role on the performance of electronic devices. This can be controlled for by designing electronic components with materials that operate suitably under the working conditions of a device. Humidity is a highly variable factor that is unavoidable in ambient conditions, capable of affecting the electrical performance of components especially when they are hydrophilic in nature. Components with such properties can allow water molecules to either permeate through or reside on the circuit surfaces over time. Due to this, it is expected that the relative humidity in the environment of hydrophilic components will vary the circuit’s performance. Previous work [1] was conducted at a single humidity of 50%RH to assess the repeatability of the measured properties. In this study, interdigitated circuits were characterized using impedance spectroscopy at multiple relative humidity levels under a fixed temperature over a frequency range of 100 mHz to 10 MHz. Five interdigitated identical circuits were fabricated on a single solder coated circuit board, followed by no additional surface treatments. The circuits on these uncoated solder boards exhibit capacitive behavior at low humidity levels as expected. With increasing relative humidity, the circuit response transitions towards resistive behavior while exhibiting a reduction in real and imaginary impedance due to increased water molecule concentration at the interfaces of the circuit. Nyquist plots exhibit this transformation as the forming of a semicircle that decreases in size with increased humidity. When the impedance data is converted to the electrical modulus formalism [2], humidity increases result in the formation of peaks in the imaginary electric modulus function as shown in Figure 1. The surface topology of the different circuits, consisting of 50 electrodes each, was examined to better understand the significant effect of relative humidity on the impedance response of the circuit. Using optical and laser microscopy, it was found that the solder coat and interdigitated combs on the uncoated boards are porous in nature and have repeated units of inhomogeneous topologies, leaving many opportunities for water to gather or permeate at surfaces between the interdigitated combs. Five distinctive regions were found to repeat across the width of the circuits. Due to this, surface roughness parameters were also examined to investigate the possible link between topology and impedance response found.