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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


2019 Lake Erie Harmful Algal Bloom Seasonal Forecast 

NOAA and its research partners predict that western Lake Erie will experience a harmful algal bloom (HAB) of cyanobacteria this summer that is larger than the mild bloom in 2018. Scientists expect this year’s bloom to measure greater than a 7 on the severity index. The severity index is based on a bloom’s biomass – the amount of its harmful algae – over a sustained period. The largest blooms, 2011 and 2015, were 10 and 10.5, respectively. Last year’s bloom had a severity of 3.6 considered a mild bloom. However, the size of a bloom is not necessarily an indication of how toxic it is. For more information on the projection click here

NOS 2019 Lake Erie HAB Seasonal Outlook


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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