Harmful Algal Bloom Reports for 405 lakes in New York State (USA), with antecedent weather conditions and trophic status for each lake.

Cyanobacterial harmful algal blooms (cyanoHABs) are often associated with warm water temperatures and low wind speeds, but quantifying thresholds in meteorological conditions is challenging. In an attempt to better quantify antecedent weather conditions associated with cyanoHABs, we assembled a dataset to include cyanoHAB reports from individual lakes, as well as air temperature and wind speed data on the day of, and 5 days preceding each cyanoHAB report.
CyanoHAB reports were provided by the New York State Department of Environmental Conservation (NYSDEC) for 405 lakes for an 11 year period spanning 2012-2023. We used 4km gridded surface meteorological data to calculate antecedent weather conditions leading up to each report.
The resulting dataset includes 4,208 cyanoHAB reports from lakes of varying trophic states in New York State (USA). We calculated anomalies in daily wind speed and air temperature for each report and the five days preceding it. The dataset is formatted as a wide table, with individual cyanoHAB reports listed by row. Each row provides report-specific data to include the date, site, trophic state of the lake, and the cyanoHAB report status. Each row contains weather data specific to the date and location of each report, with weather variables calculated from the closest grid point for each lake site. We provide 36 columns containing weather variables for each report to include air temperature and wind speed for the day of the HAB as well as the 5 days preceding it. We also provide a 24-year mean value for the day of the year (DoY), as well as the calculated difference between the day in question and the 24-year mean for the DoY.