The Salinity and Stratification at the Sea Ice Edge (SASSIE) project is a NASA experiment that aims to understand how salinity anomalies in the upper ocean generated by melting sea ice affect sea surface temperature (SST), stratification, and subsequent sea-ice growth. SASSIE involved a field campaign that sampled the transition from summer melt to autumn ice advance in the Beaufort Sea during August-October 2022, making intensive in situ and remote sensing observations within ~200 km of the sea ice edge. This dataset contains in-situ profiles of upper ocean temperature and salinity taken with a Shipboard Underway Conductivity-Temperature-Depth instrument (uCTD). A total of 2,246 profiles were taken over the sampling period, with mean depth of 100 m and mean horizontal spacing between profiles of ~800 m. Profiling with the uCTD typically occurred as the ship was moving at 1-3 m/s. For higher sea ice concentrations (10-30 %), the ship stopped every ~30 minutes to collect a profile. The measurements have been gridded onto a uniformly spaced 0.1 dbar grid from the sea surface to 200 dbar seawater pressure, and collected into a single netCDF file, where each observation in the time dimension corresponds to a single cast.