Experimental Great Lakes Waterspout Forecast

The experimental Great Lakes waterspout forecast displays waterspout potential using the Szilagyi Waterspout Index (SWI). The SWI ranges from -10 to +10, where values greater than or equal to zero represent conditions favorable for waterspout development. Only values of SWI that are equal to or greater than zero are plotted on the forecast maps.

Note that these maps are experimental. To help verify and improve this model, please send us your waterspout reports to our Facebook page or Twitter.

Waterspout forecasts will resume on August 1, 2017