This data set consists of surface-based radiometer (SBR) brightness temperatures of the snow surface and vegetation at Grand Mesa, CO, USA, acquired during NASA's 2017 SnowEx campaign. Four SBRs were deployed in the field and obtained measurements at 89, 37, 19, and 10.67 GHz in both vertical (V-pol) and horizontal (H-pol) polarizations. Data are available for 37 locations across Grand Mesa collected over five days in February, 2017. They include both 2-4 minute observations and 20 minute, continuous measurements during surface melt, with the latter designed to capture the brightness temperature increase caused by the presence of liquid water in the snow. This data set also contains snowfork measurements of snow wetness for 13 sites.