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Now Available: Enhanced Gulf of Mexico Harmful Algal Bloom Forecasting Products

Forecasts are higher resolution, providing hourly observations at the individual beach level.

A screenshot of a map showing central Florida with respiratory conditions at beaches on the Gulf of Mexico coast indicated by blue, yellow, orange, and red in order of increasing respiratory risk

One of three online Gulf of Mexico harmful algal bloom products now available to the public, the respiratory irritation forecast displays conditions at individual beaches over the next 30 hours. It is updated every three hours with any new information and supported by volunteer citizen scientists. Respiratory irritation risk is indicated by the color of the pins: blue (absent or low risk), yellow (low risk), orange (moderate risk), and red (high risk).

Harmful algal bloom in Texas, Gulf of Mexico

In the Gulf of Mexico, some harmful algal blooms (HABs) are caused by the microscopic algae species Karenia brevis, commonly called red tide. These blooms can produce toxic chemicals that affect both marine organisms and humans, creating the potential to kill marine life. In humans, red tide can lead to respiratory illness and eye irritation. Toxins can also accumulate in shellfish tissue and often lead to shellfish bed closures. NOAA issues HAB forecasts to support the decisions of coastal resource managers, public health officials, and research scientists. Forecasts also help beachgoers identify where and when coastal areas may be temporarily affected by a bloom. Visit our harmful algal bloom portal for regional information, links, and resources.

NOAA’s newly enhanced HAB forecasts are now available to the public in real time. The forecasts are higher resolution, providing hourly observations at the individual beach level. Analysis of "red tide" algal bloom locations and reported impacts are now automated, and reports include forecasts of potential development, intensification, transport, and impacts of algal blooms. The interactive dashboard from the National Centers for Coastal Ocean Science displays the following products:

  • Respiratory Irritation Forecast: Provides an estimate of the risk of respiratory irritation at individual beaches over the next 30 hours. It is updated every three hours with any new information and is supported by volunteer citizen scientists equipped with the HABScope tool.
  • Intensification Forecast: Shows the likelihood that a bloom will develop or change and displays animated coastal bloom initiation and intensification. It is based on modeled oceanographic conditions. Offshore winds and upwelling are responsible for bloom formation and intensification at the coast when the bloom begins.
  • Real-time Satellite Imagery: Shows bloom location and extent using images from the Copernicus Sentinel-3 Ocean and Land Colour Instrument (OLCI). Colored circles overlaid on the satellite imagery indicate concentrations of K. brevis cells in seawater samples provided by several sources to help confirm blooms.

For the state of Florida, the new website includes additional partner resources. The Beach Conditions Reporting System at Mote Marine Lab provides up to twice daily reports of various conditions at the beach, including respiratory irritation, visible dead fish, surf conditions, and more. State of Florida Observations show the concentration of K. brevis cells provided by the Florida Fish and Wildlife Conservation Commission monitoring program, from water samples over the last 8 days. It gives current red tide status and links to additional maps and graphics.

In addition to visiting the new website, you can subscribe to Gulf of Mexico forecasts to receive alerts and updates. Email notifications will be sent to subscribers when a bloom forms, weekly during a bloom, and when bloom conditions change. For a detailed explanation of features, view the Gulf of Mexico HAB Forecast Guide.