What does an El Niño winter mean for Florida red tide?

Florida’s west coast has dodged a red tide outbreak so far this fall. But researchers say warm waters and extra rainfall this winter could fuel a bloom if the algae does appear.

Florida’s Gulf Coast is approaching the end of an above-average hurricane season and record marine heat, but it’s been a lackluster fall for what’s become a common beachgoers’ experience: red tide.

Last year, Tampa Bay-area red tide outbreaks started in November and lasted through the winter. The toxic algae kept many people off local beaches and resulted in a series of fish kills.

But this fall’s absence of Karenia brevis, the algae that causes red tide, has puzzled researchers.

An El Niño weather pattern, like the ongoing one, usually brings more rainfall to the Southeast. The National Oceanic and Atmospheric Administration is predicting a 70% chance of above-average rainfall there this winter.

In Florida, that can mean more rainwater mixes with nutrients and becomes polluted before it dumps into waterways such as Tampa Bay, the Caloosahatchee River and Sarasota Bay, among others along the Gulf of Mexico.