When a "perky blonde weathergirl" recently predicted snow pellets five days out, Donald Gansauer of Baltimore noticed: "What, specifically, causes them so that they can be forecast this far in advance?" Also called "soft hail," "graupel" or "tapioca snow," snow pellets form when super-cooled water droplets in clouds touch snowflakes and freeze to them. They occur in strong updrafts in blizzards, lake-effect or thunder snow, where surface temperatures are at freezing or just below.