Greenland Ice Sheet surface melting has increased since the 1990s, affecting the rheology and scattering properties of the near-surface firn. We combine firn cores and modeled firn densities with 7 years of CryoVEx airborne Ku-band (13.5 GHz) radar profiles to quantify the impact of melting on microwave radar penetration in West Central Greenland. Although annual layers are present in the Ku-band radar profiles to depths up to 15 m below the ice sheet surface, fluctuations in summer melting strongly affect the degree of radar penetration. The extreme melting in 2012, for example, caused an abrupt 6.2 ± 2.4 m decrease in Ku-band radar penetration. Nevertheless, retracking the radar echoes mitigates this effect, producing surface heights that agree to within 13.9 cm of coincident airborne laser measurements. We also examine 2 years of Ka-band (34.5 GHz) airborne radar data and show that the degree of penetration is half that of coincident Ku-band.