In this study, a relative humidity sensor based on a metamaterial consisting of electric-inductive capacitive resonators and a commercial polyimide band on top of a transparent copper-backed substrate is designed for C band satellite communication frequencies. The resonance frequency of the metamaterial is estimated by an equivalent circuit approach. Later, the spectral response is characterized by three-dimensional electromagnetic simulations. The effect of the gap width of the electric-inductive capacitive resonator on the sensitivity of the relative humidity is investigated. It is found that decreasing the gap width of the resonators has a positive effect. On the other hand, increasing the thickness of the polyimide band did not show any enhancement on the sensitivity value. The designed sensor has potential to be used for tracking climate and environmental conditions. Figure A. Absolute frequency shift as a function of % relative humidity for different gap width values Purpose: A metamaterial based highly sensitive relative humidity sensor is aimed to be designed at C-band frequencies, which is suitable for tracking climate and environmental conditions. Theory and Methods: A metamaterial sensor for relative humidity sensing is designed by utilizing from equivalent circuit approach and by using a three-dimensional electromagnetic solver based on finite integration technique. Reflection spectra are calculated for relative humidity ratios of environments ranging from 0% to 100% in 5% steps. Relationship between the shift of the resonance frequency and relative humidity change is put forward for structure parameters. Results: The metamaterial comprising of electric-inductive capacitive resonators is estimated to show a resonance at 8.38 GHz by the equivalent circuit approach and at 8.57 GHz by the numerical analysis. When the metamaterial is coated with a commercial polyimide band, Kapton HN, the resonance frequency is shifted to 7.00 GHz with-36 dB attenuation. Surface current distribution over the metamaterial unit cell at the resonance frequency is investigated to have a physical background of the resonance effect. The resonance linearly shifts to lower frequencies as the relative humidity is increased. Effects of the gap width of the resonator and thickness of the polyimide band on the sensitivity of the sensor are investigated. Conclusion: A metamaterial sensor having 4.07 MHz/RH of relative humidity (RH) sensitivity is demonstrated numerically for C-band meteorology applications. It is found that the sensitivity of the metamaterial based sensor increases for narrower gap widths since the localization of the electric field increases.