This data set contains long-wave infrared radiometer data, thermal infrared (TIR) imagery, and visible-band (RGB) imagery from the February 2020 NASA SnowEx field campaign flights over the Grand Mesa, CO. These data are from the center, nadir-viewing radiometer; center, nadir-viewing, TIR camera; or nadir-viewing, visible-band camera. Data were collected from the NASA SWESARR flights onboard the Navy CIRPAS Twin Otter. The measurements were to document the snow, forest, and land surface temperatures over targeted points of the mesa coincident with ground survey stations and can be used to study snow remote-sensing of signatures, small-scale temperature variability (sub-satellite resolution), diurnal snow temperature variability, effects of forest cover, and thermal snow budgets.