The Mississippi Sound (MSS) is a very productive brackish environment that has historic, cultural, and economic importance for the region. Over the past decades, natural and anthropogenic sources have negatively impacted the MSS through hurricanes, oil spills, and influxes of sediment-rich freshwater from various watersheds. Lake Pontchartrain and Mobile Bay, fresh to brackish bodies of water, feed into the Sound, which can additionally contribute to the variability of different water quality parameters. Understanding where and when these parameters vary within the MSS will allow for informed water quality management. This study performed data collection in 25 locations in the MSS from Bay St. Louis to Biloxi Bay in various months of 2023/2024/2025 to characterize the seasonal variability of water quality parameters in addition to utilizing remote sensing to create monthly satellite-based water quality parameter concentration maps. Surface water sampling and radiometric measurements were performed from 8:00 AM to 1:00 PM during clear-sky days. TriOS sensors recorded water-leaving radiance, sky radiance, and solar downwelling irradiance to estimate water surface reflectance. Other in-situ data (turbidity, pH, dissolved oxygen, conductivity, water temperature) were collected using a YSI 4-probe sonde. Additionally, date, time, GPS location, sky and water surface conditions, Secchi depth, water depth, air temperature, and wind speed were collected utilizing various devices. Eight liters of water from each point were collected, filtered, and analyzed in the lab for colored dissolved organic matter, total suspended solids, transmittance and reflectance, chlorophyll-a, and phycocyanin using spectroscopy. As a result, concentration maps using Sentinel-3 Ocean and Land Cover Instrument (OLCI) imagery were produced to visualize the spatial and temporal distribution of water quality parameters on the in-situ data. These results demonstrated that the peak turbidity and total suspended sediment concentration occur during summer, while chlorophyll-a and phycocyanin concentrations remained low or insignificant over time. Secchi disk depth showed an increasing trend from the coastline to offshore points. Colored dissolved organic matter values were homogenous and low among the samples. Collection of such data sets and maps can be utilized by other researchers, agencies, and water quality/resource managers to train remote sensing or hydrologic models, identify critical areas for monitoring stations, or target watersheds for enhanced management practices.