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Experimental Freezing Spray Guidance

Basin

Alaska  Atlantic  

Forecast hour

12  24  36  

Modified Overland (US algorithm in cm/hr) Stallabrass (Canadian algorithm in cm/hr)

The Overland* and Stallabrass images above depict the forecast ice accumulation rate (in cm/hour) at 12 hours, 24 hours, and 36 hours. The rate is an instantaneous forecast, not cumulative.

The guidance is based on the Global Forecast System (GFS) model data.

*More information on the Fetch Factor applied to Overland freezing spray algorithm (pdf).