Sargassum Peak Passes, Sparing South Florida Beaches a Second Record Year

The rafts of brown seaweed that carpeted South Florida’s shoreline for much of the summer are finally in retreat. Scientists with the University of South Florida’s Sargassum Watch System say this year’s inundation has peaked, and 2026 is now expected to finish second all-time for the tonnage of sargassum washing onto beaches, short of a new record.

Brian Barnes, the lead scientist tracking the great Atlantic sargassum belt, said the update deflates earlier concerns that this summer would surpass last year’s record-setting, beach-spoiling season. Consistent with the pattern seen in most previous years, total sargassum in every region of the Atlantic began declining in July while its distribution held stable.

That is cold comfort for the tri-county coast, which sat squarely in the seaweed’s path. Beach trackers reported that Florida’s Atlantic side took the hardest hits this year, with Miami Beach, Fort Lauderdale, Palm Beach and the ocean side of the Keys seeing the worst accumulations, while the Gulf coast stayed largely clear.

A Strange Kind of Spectacle

Sargassum is a leafy, rootless alga that drifts across the open ocean in vast floating mats, sheltering crabs, shrimp and juvenile fish along the way. The trouble starts onshore, where mounded seaweed decomposes into a sulfurous stench that can clear a beach faster than an afternoon thunderstorm.

It also produces some of the most surreal coastal imagery in Florida: golden-brown windrows stretching to the horizon, front-end loaders working the sand at dawn, and turquoise water fringed in amber. Drone photographers have documented the belt’s arrival each summer as it snakes from the coast of Africa through the Caribbean and up the Florida Straits.

With the peak behind it, South Florida can expect gradually cleaner sand through the fall as beach crews work down the backlog. Researchers caution, though, that the sargassum belt has trended dramatically larger over the past decade and a half, meaning the seaweed-framed postcard view is likely to remain a fixture of South Florida summers for years to come.