Sargassum Seaweed 2025 Forecast Florida. The southeast coast of florida, including the florida keys, will be largely free of sargassum until late may, according to the university of south florida's march sargassum outlook bulletin. Sargassum washed ashore on a beach in the caribbean during the summer of 2023, and seaweed researchers at the university of south florida have documented.
In a normal year, the sargassum seaweed “season” in florida begins in april and continues through summer. The size of this upcoming summer’s.