HAB Forecasts


Our HAB forecasts alert coastal managers to blooms before they cause serious damage. Short-term (once or twice weekly) forecasts identify which blooms are potentially harmful, where they are, how big they are, and where they're likely headed. Longer-term, seasonal forecasts predict the severity of HABs for the bloom season in a particular region.

Early warning provides health officials, environmental managers and water treatment facility operators information to focus their testing to guide beach and shellfish bed closures or water treatment in a more appropriate timeframe. They also allow the seafood and tourism industries to minimize impacts.

HAB forecasts are based on understanding the causes of HABs and how they respond to changing weather and ocean conditions. The other critical component of a HAB forecast is the ability to routinely and remotely detect HABs, their toxins, and environmental conditions that foster blooms and enhance their toxicity.

NCCOS supports the development of seasonal and weekly HAB forecasts in collaboration with academic, state, and local partners. Like weather forecasts, HAB forecasts identify the potential risk of exposure to hazardous conditions (e.g. HAB toxins) to inform decisions that protect public health. These efforts span each U.S. coastal region affected by HABs, including the Great Lakes. NCCOS has pilots including satellite monitoring, which can be found at the HAB monitoring system web site.

Once pilot forecasts are developed and validated, the forecasting ability is transitioned to operations, often as part of the NOAA HAB Operational Forecasting System (HABOFS). NOAA provides operational forecasts for HABs in Lake Erie and the Gulf of Mexico. NCCOS is currently funding research in support of pilot regional HAB forecasts in the Gulf of Maine (Alexandrium) and the Pacific Northwest (Pseudo-nitzscha), including Puget Sound (Alexandrium). Past NCCOS funding led to the development of the California Harmful Algae Risk Mapping (C-HARM) forecast model now available at NOAA CoastWatch.

2020 Western Lake Erie Projections

Western Lake Erie has been plagued by an increase of HABs intensity over the past decade. These blooms consist of cyanobacteria or blue-green algae, which are capable of producing toxins that pose a risk to human and animal health, foul coastlines, and impact communities and businesses that depend on the lake. The early season projection estimates bloom severity based on Maumee River discharge and modeled phosphorus loads. It is issued weekly from May until the seasonal forecast is announced. The final seasonal assessment will be completed by November 2020.  

2020 Lake Erie Seasonal Forecast Event

The official seasonal forecast for Lake Erie was announced on July 9 during a live webinar hosted in collaboration with Ohio Sea Grant. For the NOAA Press Release, click here

Lake Erie HAB Forecast

NOAA has issued forecasts for HABs in Lake Erie starting as a weekly experimental product in 2009. The forecast is now issued twice weekly during the bloom season, typically July through October. Lake Erie HAB Forecast information is available here. Also, the imagery for the Lake Erie forecast has recently changed to a new color scale, as explained here.

For other data on Lake Erie HABs, visit one of these websites:

For safety information on these blooms, visit the Ohio EPA website.

Florida Karenia brevis "red tide" forecast, Sanibel and Pinellas

With our partners at the Gulf of Mexico Coastal Ocean Observing System (GCOOS), we have started providing forecasts of respiratory irritation in some areas of Southwest Florida. The irritation can cause coughing, watery eyes, and a runny nose, but can be more dangerous to asthmatics. (FDOH) The blooms are patchy and the winds change through the day, so accurate forecasts can allow people to find times and places they may enjoy the beach. To see the respiratory forecasts that are currently available, go to the forecast page

In addition, we are now posting satellite data for Florida in the HAB Monitoring System. This new information helps identify areas that should be monitored. We are using new satellites, the two Copernicus Sentinel-3 satellites.

To make the respiratory forecasts, we use measurements of the number of Karenia cells in a water sample. Combining these "cell counts" with wind forecasts in a model for respiratory irritation, we can estimate the likelihood of experiencing respiratory irritation. These measurements, or counts, either come from state or county labs counting by eye through a microscope, or from a new system called the HABscope. The HABscope allows measurement from the beach, without going to a lab. A pocket tablet computer is connected to a standard student level microscope (using a 3-D printed eyepiece adapter). A 30 second video is taken and uploaded by cell phone to a GCOOS computer that uses feature recognition software to find the cells. Unlike many types of microscopic algae (phytoplankton), Karenia brevis swims. We use that to help count the cells. Cell counts are combined in a model developed in NOAA and posted to the HABscope web site.

We use cell count measurements from Pinellas County, and have started HABscope monitoring on Sanibel Island. For more information on HABscope you may also see this paper.