The airborne SWE Synthetic Aperture Radar and Radiometer (SWESARR) instrument was developed at NASA Goddard Space Flight Center. SWESARR has three active (including a dual Ku band) and three passive bands. Radar data is collected in dual polarization (VV, VH) while the radiometer makes single polarization (H) observations. The combination of all these microwave measurements will provide an important data set to develop and to enhance SWE retrieval algorithms.