Lake Erie Harmful Algal Bloom Bulletin

Provided by NOAA's National Centers for Coastal Ocean Science (NCCOS)

Please find up-to-date analysis, satellite imagery, and forecasts at the Lake Erie Harmful Algal Bloom Forecast.

This is a reminder to check the Lake Erie HAB Forecast, linked above.

Cloudy conditions have limited satellite imagery over western Lake Erie for the past several days. As of 19 July 2025, satellite imagery showed patches of cyanobacteria in Maumee Bay.

Sandusky Bay continues to have a local, widespread bloom of mixed cyanobacteria.

This bulletin provides a summary and forecast of the Microcystis harmful algal blooms (HABs) in western Lake Erie. Updates will be e-mailed to subscribers with important information regarding bloom status and significant features. For a detailed explanation of the products on the forecast website, view the Lake Erie HAB Forecast Guide.

Click here to subscribe to the HAB forecasts and seasonal projections for Lake Erie

Please email questions and comments to hab@noaa.gov.

- NCCOS HAB Forecasting Team

Interpreting the Forecast System:

• Forecast System Guide: For a detailed explanation of the Lake Erie Forecast System, view the Lake Erie HAB Forecast Guide
• FAQ's: For Frequently Asked Questions about cyanobacteria and the forecasts NOAA issues, view the FAQs Page

Health Information:

• For HAB safety information, please visit Ohio EPA
• For current HAB conditions at Lake Erie Beaches, please visit Ohio DOH BeachGuard

Additional HAB monitoring and forecasts:

• NOAA NCCOS HAB Monitoring System
• NOAA NCCOS HAB Forecasting

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