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Lake Erie Harmful Algal Bloom (HAB) 

Bulletins are produced during the HAB season, typically starting in July and lasting into early fall. NOAA provides forecasts of blue-green algae, or cyanobacteria blooms in Lake Erie in the form of bi-weekly bulletins. Not all algae are harmful, however some cyanobacteria blooms can grow rapidly and produce toxins that cause harm to animal life and humans so they are called harmful algal blooms (HABs). Lakeshore communities can use NOAA's forecasts as a decision making tool. NOAA bulletins provide analysis of the location of HABs, as well as 3-day forecasts of transport, mixing, scum formation, and bloom decline. To receive the bulletin via email, please sign up by clicking here

NOAA HAB Forecast Bulletin


2020 Lake Erie Harmful Algal Bloom Early Season Projection 

NOAA projects that the Lake Erie algal bloom in summer 2020 will be smaller than last year (2019), with a likely severity between 3 and 5. Uncertainty in the models and forecasts indicate a potential severity of up to 6 (less than 7.5 seen in 2019). The models include rain events that are expected through early June. There is still uncertainty in the projected maximum severity because of limitations in forecasting the exact location and amount of rainfall. As we add data over the next month, this uncertainty will decrease. Any bloom that develops will change with time and move with the wind; we will provide information on the presence and location of the bloom throughout the summer. 

NOS 2020 Lake Erie HAB Early Season Projection


For more info and links about harmful algal blooms please visit  CO-OPS.

This web page is being provided as part of a multi-agency effort to provide information about and access to existing forecasts of Harmful Algal Blooms and other environmental information.  Information/products are provided by NOAA/National Ocean Service, NOAA/Office of Atmospheric Research/GLERL, and NOAA/National Weather Service. Please visit web pages for those agencies for detailed information about the operational status of these products and contacts for questions about these products.


For more information see the Product Description Document.

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