The response of the continental shelf from Louisiana to Alabama to Hurricane Nate and tropical storm Alberto Understanding the sea state changes that resulted from the events Nwankwo Uchenna, Howden Stephen, Brian Connon, Dmitri Netchaev The Department of Marine Science The University of Southern Mississippi Stennis Space Center, Mississippi, U.S.A [email protected] Abstract— The Central Gulf of Mexico Ocean Observing System (CenGOOS) in the Division of Marine Science of the School of Ocean Science and Engineering at the University of Southern Mississippi is part of the Gulf of Mexico Coastal Ocean Observing System (GCOOS). They manage a variety of CenGCOOS buoys and both long and short range High Frequency Radars (HF) in the northern Gulf of Mexico. One of the sensors on the buoys is a survey grade Global Navigation Satellite System receiver and antenna. This is used for reducing water level to a reference datum. The HFR radar provides surface current information in the Mississippi Bight from the Mississippi River delta to Destin in the Florida Panhandle shelf. If tropical storm force winds are forecasted to strike a station within 72 hours, that HFR station is removed as a precautionary measure. However, they are left operational when the events do not pose to be a danger to the stations. Using the GNSS records from two buoys (USM3m01 deployed at Mississippi shelf and USM3m02 deployed at Louisiana shelf), the changes in sea level that resulted from Hurricane Nate and tropical storm Alberto are analyzed and compared to outputs from satellite altimetry. Furthermore, changes in circulation patterns for the region are analyzed using the surface current data from the HF radar. Additional insights about the Hurricane and tropical storm were extracted from gridded satellite wind and temperature data. Keywords—High Frequency Radar; Global Navigation Satellite System; Hurricane Nate; Tropical Storm Alberto; Northern Gulf of Mexico .