We performed hourly monitoring of precipitation and soil moisture at the Two Towers landslide located in northern California near the town of Zenia. Data were acquired January 19, 2017 to April 29, 2020. Rainfall was measured near the center of the landslide using a tipping-bucket rain gauge with resolution of 0.254 mm and accuracy of ±2% to 250 mm/h (resolutions and accuracies stated herein are as specified by sensor manufacturers and accounting for datalogger resolution). Soil moisture (volumetric ratio of water volume to total volume; unitless) was measured near the center of the landslide using a dielectric sensor installed at 19-cm depth into the wall of a hand-excavated pit that was subsequently backfilled using material obtained during excavation. The soil-moisture sensor utilized factory calibration and has resolution of 0.001 and accuracy of +/- 0.03. These data support a study described in Liao, T.-H., Kim, S.-B., Handwerger, A.L., Fielding, E.J., Cosh, M., and Schulz, W.H., 2021, High-resolution soil moisture maps over landslide regions in northern California grassland derived from SAR backscattering coefficients: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 10.1109/JSTARS.2021.3069010.