Voyager spacecraft radio, interplanetary plasma, and interplanetary magnetic field data are used to show that large-amplitude fluctuations in the power generated by the Saturn kilometric radio emission are best correlated with solar wind ram pressure variations. In all, 13 solar wind quantities previously found important in driving terrestrial magnetospheric substorms and other auroral processes were examined for evidence of correlations with the Saturn radio emission. The results are consistent with hydromagnetic wave or eddy diffusion processes driven by large-scale solar wind pressure changes at Saturn's dayside magnetopause.