Presented at the 2020 Ocean Sciences MeetingAn extremely small, low mass Lagrangian buoy platform is under development to provide continuous and extended-duration monitoring of near-surface salinity (12 cm depth), near-surface temperature (3 cm depth) and directional sea state parameters (i.e., significant wave height, peak spectral period and mean wave direction). This poster describes preliminary results from a laboratory experiment campaign performed at the University of Miami ASSIST wind-wave-current flume. These and other experiments are used to characterize the influence of physical processes (such as bubble plumes and rainfall) on salinity measurement. Results are incorporated into data acquisition and processing algorithms as well as uncertainty analyses for the buoy science measurements. Newly revised data products from one buoy deployed during the Salinity Processes Upper-ocean Regional Study in the tropical Pacific (SPURS-2) field campaign are highlighted, including analysis of several rain events and the buoy drift velocity characteristics. Advantages of this platform include: 1) measurements are nearly continuous with high temporal resolution allowing characterization of multiple time-scale events, 2) low cost and 3) easily deployed. It is anticipated this buoy platform would be useful characterizing satellite subfootprint variability in regions with significant rainfall where horizontal inhomogeneity develops but is relatively short-lived and in high-latitude cold water regions where L-band radiometry is less accurate and deployment of valuable research-grade instrumentation may not be desirable. Furthermore, given the potential for air-drop deployment, we envision multiple buoys could be released near the sea-ice edge or in glacial fjords in association with ice thickness measurement overflights to better remotely characterize freshwater surface plumes associated with melting and calving events.