Kyne, D., 2023. Storm surge risk assessment in coastal communities in the Rio Grande Valley: An application of GIS-based spatial multicriteria decision analysis with analytical hierarchy process. Journal of Coastal Research, 39(3), 471–483. Charlotte (North Carolina), ISSN 0749-0208. Cameron County, which is located in the Rio Grande Valley, maintains records of storm surges associated with noticeable property damage, fatalities, and injuries. This study investigates storm surge inundation risk in Cameron County using storm surge hazard datasets from the National Oceanic and Atmospheric Administration, along with American Community Survey 2019 block group datasets. Using a GIS-based spatial multicriteria decision analysis with an analytical hierarchy process method, the study estimates that storm surge water levels could be above 6.1 m (20 ft) in category 4 and 5 hurricane events, whereas about 37% of the county's population (159,659 people) could be exposed to floodwater in the event of a category 5 hurricane. The inundation risk map shows that in the event of a category 4 or 5 hurricane, about 28 and 42%, respectively, of county's area could be exposed to a very high level of inundation risk. Because of the destructive power of such storms and their potential consequences, the findings suggest that storm surge risk should not be underestimated. All stakeholders should proactively prepare for potential storm surge events.