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Harmful Algal Bloom Forecasts

Harmful algal blooms (HABs), the rapid growth of algae, can produce toxins that have harmful effects on people, fish, marine mammals, birds and local economies. NOAA's Center for Operational Oceanographic Products and Services (CO-OPS) provides routine HAB forecasts to help members of the public make informed decisions when a bloom is temporarily affecting their area. The forecasts also aid people responsible for responding to bloom impacts.

  • Gulf of Mexico HAB Forecast
    Beginning in August, when conditions typically become favorable for a HAB of the red tide species, Karenia brevis, CO-OPS issues weekly forecasts for the eastern and western Gulf of Mexico. Twice-weekly forecasts are released during a bloom with additional updates when conditions change.

  • Lake Erie HAB Forecast
    CO-OPS issues twice-weekly forecasts for Lake Erie after sampling confirms presence of the HAB species Microcystis, released only during bloom season (typically July to October) when conditions are optimal for growth.

  • More information related to Operational HAB Forecasts:


Blooms of harmful algae like this one off the coast of Texas
Blooms of harmful algae, like this "red tide" off the coast of Texas, can cause illness and death in humans and animals.