In January 2018, a U.S. Geological Survey (USGS) team collected short cores and surface samples from four islands in Florida Bay, Everglades National Park, south Florida (Wingard et al. 2019). The 2018 samples were collected approximately five months after the passage of Hurricane Irma on September 10, 2017, as a category 4 storm. The four islands had also been cored in 2014. The goal of the long-term study of these four islands is to examine the impacts of climate and sea level on island formation and resilience, and to provide insights into the stability of the south Florida coastline. The passage of Hurricane Irma provided an opportunity to sample sediments deposited by the storm surge. The particle size analysis (PSA) data presented here contain results from three types of samples: 1) a short core (20 cm) collected from the western-most of the four islands (Jim Foot Key); 2) surface samples, representing overwash deposits from the storm surge collected from the four islands (Jim Foot Key, Buttonwood Key #7, Bob Allen Key, and Russell Key); and 3) basin samples from Florida Bay mudbanks and deeper water surrounding the islands. The basin samples were collected in December 2020 for comparison to the storm deposits to investigate possible provenance. The three types of samples were photographed and described prior to splitting and/or subsampling for PSA, which was conducted using the Beckman Coulter LS 13 320 XR laser diffraction analyzer housed in the Bascom Laser Diffraction Sedimentology Laboratory in Reston, VA. The work described here is done in collaboration with Everglades National Park (Study #EVER-00617) and is funded by the Greater Everglades Priority Ecosystem Science program of the USGS. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Reference: Wingard, G.L., Bergstresser, S.E., Stackhouse, B.L., Jones, M.C., Marot, M.E., Hoefke, K., Daniels, A., and Keller, K. 2019. Impacts of Hurricane Irma on Florida Bay Islands, Everglades National Park, U.S.A. Estuaries and Coasts. https://doi.org/10.1007/s12237-019-00638-7 This Data Release was revised to v1.1 in May 2025 to include updated statistics data for laser diffractometry results contained therein. No other changes to the data release were made for v1.1.