Red tide, a type of marine algae that undergoes an explosive growth and begins producing toxins, typically occurs off Florida’s southwest coast every year between late summer and fall and spring. Due to currents and winds, some tides never reach shore. But this year’s tide, Florida Department of Environmental Protection officials say, is the worst since the last big tide in 2006, that lasted for more than a year and a half and killed more than 250 manatees. Weather forecasters expect hazardous beach conditions to last at least through Thursday, according to the Fort Myers News-Press.