This product takes several types of radar output and blends it for one easy to use tool that enables you to see where hail of all sizes is possible. Generally, hail between 0 and 2.5cm (0-1”) is regarded as small and less dangerous while hail in excess of 1” is something to take more seriously. In the US, hail above 1” in diameter is considered “severe” and warnings will be issued from the NWS if such a storm develops.
