Harmful Algal Bloom Forecasts

Gulf of Mexico Harmful Algal Bloom Forecast

In the Gulf of Mexico, some harmful algal blooms are caused by the microscopic algae species Karenia brevis, commonly called red tide. Karenia brevis blooms can cause respiratory illness and eye irritation in humans. It can also kill marine life, and lead to shellfish closures. Blooms are often patchy, so impacts vary by beach and throughout the day. NCCOS monitors conditions daily and issues regular forecasts for red tide blooms in the Gulf of Mexico and East Coast of Florida. You can find the forecasts below, and up-to-date conditions here.

Florida - Current Conditions


Karenia brevis (red tide) is present along the coast at concentrations that may cause respiratory irritation with onshore winds in COLLIER, LEE, MANATEE, PINELLAS and SARASOTA counties.
A MODERATE to HIGH risk of respiratory irritation is most likely when winds are blowing onshore or alongshore, and less likely when winds are blowing offshore. Check links below for detailed forecasts at individual beaches.


Respiratory Forecast*

Modeled forecast of respiratory irritation at individual beach locations, based on field samples of Karenia brevis concentration, wind speed, and direction.

Intensification Forecast

Model results estimating the likelihood of bloom initiation or intensification along the coast of Southwest Florida, due to an accumulation of cells at the coast.

Satellite Imagery

Current imagery from the Ocean Land Color Imager (OLCI) showing bloom location and extent.

Economic Analysis of Shoreline Treatment Options for the Seacoast Region of New Hampshire

Beach Conditions Reporting System

Provides today’s conditions at multiple beaches along the west coast of Florida, this includes respiratory irritation, rip currents, wind, and others.

Economic Analysis of Shoreline Treatment Options for the Seacoast Region of New Hampshire

State of Florida Observations

State of Florida (FWC-FWRI) bloom status updates and 8-day interactive map of statewide K. brevis cell concentrations in water samples.

Texas - Current Conditions


There is no risk of respiratory irritation from Karenia brevis (red tide) at this time.


Respiratory Forecast*

Potential respiratory irritation over the next two days

Satellite Imagery

Current imagery from the Ocean Land Color Imager (OLCI) showing bloom location and extent.

*Citizen science volunteers use HABscope to assist NCCOS in monitoring conditions. The collection of HABscope information from those volunteers is authorized under the OMB Control Number included in the Citizen Science & Crowdsourcing Information Collection page.

HAB Alerts

HABs in the Gulf of Mexico pose a risk to human and animal health, foul coastlines, and negatively impact communities and businesses. Subscribe to receive Gulf of Mexico HAB updates via email.

More information related to HAB Forecasts: